Weaver II (including Weaver II Pro) settings are not compatible with Weaver Xtreme. You need to convert your Weaver II settings to Weaver Xtreme. Below is a step by step procedure to convert Weaver II (pro) and Aspen sites to Weaver Xtreme.

Note: This was actually written for weaver II (Pro) conversion, but should be applicable to Aspen with little differences

You should read the whole document first, as well as visit the Xtreme demo site http://demo.weavertheme.com/ ) to get a view of Xtreme before starting the process.

Important:
Before converting, you should make sure you are running the latest version of Weaver II or Weaver II pro.
To download the latest version of Weaver II Pro, go to
Weaver II pro Download page
login with your Weaver II Pro credentials (note that these are different to your Weaver Xtreme login credentials).
Once logged in, you can download Weaver II Pro 2.2.3.
To download the latest version of Weaver II, go to

Download

0) Clone Your Site

If you are converting a live site, perhaps the best way to the conversion is on a cloned site. It is now very easy to make a complete duplicate of your live site on a subdomain or subdirectory of your original site.

To me, the only way to clone a site now is with the plugin All-in-One WP Migration.

It does everything for you. Taking a bit of time to read the directions will save you tons and tons of time duplicating a site.

i’ve used it several times, and it is just amazing.

1. First, clean up your site. Delete old versions of posts and pages. Clean out your Media Library of old and duplicate content if possible. These steps aren’t essential, but will reduce the database and media storage size, and make your site smaller and more efficient.
2. Create a working version of WordPress for the migration target site. This can be just a the simple default WP starting site as the migration will replace all the old content.
3. Install All-in-One WP Migration on both the original site and new target site
4. Open the All-in-One WP Migration from the Dashboard menu. You then export your current site to a file – this can be downloaded to your own computer or saved on various file servers such as Dropbox. Then go to the new target site as an admin, and import the exported file to the new site.
5.  The entire process is really very easy, and your site will be auto-magically moved to a new URL. The migration will fix links and old URL, but not rename the text for links. There is an option during export to change specific fix if you wish (e.g., “My Current Site” to “My Great New Site”).
6. After conversion, you can then migrate back to the original URL.
7. As a bonus, the export process creates a backup of your existing site.

1) Preparation

a- Database backup
First Download a full backup of your site including the database. There is really no risk in the conversion process, but some of it involves making permanent changes in the database so you are always better safe than sorry. If you cloned your site, this step isn’t really necessary.

b- Settings file
Within the Admin of your Weaver II site, go to save restore, and click on Download ALL settings (w2b file). You will need this file for the conversion, and it will also be a good backup to keep in case you did need to restore the weaver II site.

c- Widgets
One thing WordPress messes up when switching theme are widgets. You should go in Appearance > Widgets, open each widget area and take a note of what widgets are in each of them.

d- Shortcode content
Until Weavers Shortcode conversion plugin is done, gather content from things like Social icons, Link Buttons, Shortcoder…
EDIT: the plugin is now available https://wordpress.org/plugins/weaver-themes-shortcode-compatibility

e- Theme and Plugins

• In Appearance > Theme > Add new, Search for Weaver Xtreme, and Install the theme. Do Not Activate yet.
• In Appearance > Plugins > Add New, Search For Weaver Xtreme Theme Support, and install the Weaver X Theme support plugin. Do Not Activate yet.
• If you bought the “Plus” Plugin, in Plugins > Add New , Download and install the “Plus” Plugin Zip file you downloaded for the site you bought it from. Do Not Activate yet.
• In Plugin, Search for “Weaver Theme shortcode Compatibility”  Download, install, Do Not Activate yet.
• If you used the [weaver_show_posts] shortcode, you want to search for “Weaver Show Posts” (used to be ATW Show posts), Download, Install AND Activate.

And finally (and most importantly), get the Weaver II to Weaver Xtreme plugin. This plugin is available from the WordPress repository Weaver II to Xtreme Conversion Plugin.  Click the previous link to download the plugin, then upload AND activate it from the Appearance > Plugins > Add New > Upload menu.

2) Converting Settings

A- First read through the Plugin Help page in Tools > Weaver Converter > Help (from the main WordPress left menu bar)

B- Then in the Main Plugin page Tools > Weaver Converter > Conversion option section, you can browse to the w2b setting file you just downloaded, and click “Upload convert theme/backup” to convert the setting file.
After the conversion is done, you get a detailed list of the conversion result. That lists will also be available after you have transitioned to Xtreme.

Note 1: The Setting conversion does not do anything to your site, it just creates a New Xtreme Setting file that you can then download and use once you will have activated Xtreme.

C- Next click “Download” to actually download the Xtreme setting file (wxb file).

D- Then click the Download button below that downloads converted shortcodes settings for the “plus” plugin.

Note 2: The next section of the converter is the “Convert Per Page and Per Post Settings “. This section will actually modify your pages options to match Xtreme.

If you cannot disturb your site long enough to complete all the process in one go, you will be able to go back to Weaver II at any time and have your site undisturbed. When you switch back to Weaver II (pro) it automatically loads the Weaver II settings and everything looks the way it used to.

This allows you to take your time with the settings conversion, by activating Xtreme, working on the settings, then going back to Weaver II so the site can still be viewed normally until you have time to work on the conversion some more.

3) Configuring Xtreme Settings

IMPORTANT: At any point during this process, you can go back and activate Weaver II (Pro) to check how things where under the old theme, them come back and activate Xtreme to implement a change.

a- Loading converted settings

• In Appearance > Theme, Activate the Xtreme Theme. As you do that, realize your site will no longer look correct, so do that at an appropriate time.

Note: If your site should not be disturbed, you should clone your site in a sub folder or sub domain, and execute this whole process on the cloned site first. This would allow you to finalize all the settings for the Xtreme theme without disturbing your live site, and only apply these to the live site when you have worked out all the details. If you need help with cloning your site, read the article on the subject in the FAQ http://weavertheme.com/migrate-your-site-to-new-domain-name-or-new-server/

• Then in Plugins, activate the following plugins:
  • Weaver X Theme Support
  • “Plus” if you have it. If you do, after activating the plugin, also activate the “Plus” License in Appearance >  + Xtreme plus > Activate
• Upload the Converted Settings:  This step must be done using the Customizer. Load the Customizer (Appearance : Customize). Open the General Options & Admin -> Restore Settings menu. Browse to the converted Xtreme setting file you downloaded previously after conversion, and click “Upload Theme backup”
  This will load all the converted settings.
• The Legacy Admin Appearance > Weaver Xtreme admin > Main Options > Save/Restore no longer works as of Weaver Xtreme Version 3.1.2. You must use the Customizer interface to load the converted settings file.

Note: You site probably still looks like a mess, don’t worry and read on.

b- Fixing WordPress settings
When you switch theme you lose WordPress settings, so you need to redo these manually

• Reselect your header image if you had one previously selected
• Reset your overall background image if you had use WP to do that in Weaver II
• Move your widgets back in their proper location.

The biggest mess after switching theme, is that widgets sometimes end up all over the place. You need to go to Appearance > Widgets, and move your widgets back to where they were. Some will have been moved to a different area, some will be in the unused area. Use your notes to know which one goes where.

As sidebar and other widget areas are different in Xtreme, You may need to experiment with some new choices. The biggest change may be with sidebar widgets. Xtreme has only two Sidebar widget areas, primary and secondary, that are stacked up. If you used side by side widget areas layout in Weaver II, you may need to put widgets from two weaver II sidebar widget areas in the same one under Xtreme, then use the Sidebar widget layout options to make them side by side.

c- Finalizing settings changes manually

Note: By now things should start looking better but there are still a number of things to finalize manually
1- Sidebar layouts
As explained above, you will need to reselect global sidebar layouts in Main Options > Sidebar &Layout. Don’t worry about per page layout settings for now. Note the new mobile stacking choices and take advantage of them.

2- Menus
Your custom menus will still be there, but they probably wont be allocated to primary, secondary. Go to Appearance > Menus >Manage Locations, and reselect the right menus. Note, there is now a mini menu you can allocate too.

3- Fonts.
These are handled differently in Xtreme, so you need to go in each page under Main options, and select the proper font family for each area, as well as eventually adjust the size settings. If you used google fonts, you will have to set them up in Main options > Fonts & Custom.

4- Colors
Because some areas are different in Xtreme, you may need to set some colors here and there

5- Custom CSS
If you had a lot of extra customization, this will be the major part of the work.
Custom CSS Rules in Options CSS+ Boxes will most likely be fine.
Custom CSS rules in Main Options > Fonts & Custom > Custom CSS Rule box will have to all be examined one by one to see if they are still relevant and have the right syntax.
Hopefully you had commented your custom CSS rules so you will know what each one is for. If not you will need to do some inspection with your browser developer tool 
For each rule there will be 3 possibilities

• The rule still works and still does something that is needed: Just keep it
• The rule does not work because its syntax no longer matches Xtreme and what it did is missing :
  You first need to inspect if there is now a new option in Xtreme that can do that for you. If so use the new option(s) and delete the rule.
  If there is no option(s) do to the job, you need to figure out the new syntax / selectors to use (we can help with that).
• The rule does not work, and what it did is no longer an issue > Just delete the rule.

What I found out, is that most of the tweaking rules I had in Weaver II ended up being unnecessary in Xtreme. A number of the valid rules I had did have a new option in Xtreme that I could use. All an all my Custom CSS went way down on Xtreme.
Note: This would be a good time to go to Main Options > Save Restore > Click Save Settings (to back up your Xtreme settings in the database)  

6- Customized layouts using HTML Insertion areas and widget areas (header / footer).

If you had built very customized header/footer using HTML Insertion and widget areas, you may need to revisit how it was done in the light of the new tools and areas in Xtreme. Review the Insertion area page of the demo site http://demo.weavertheme.com/insertion-areas/ and the other ones to gather Xtreme layout ideas/solutions, and eventually reproduce your design using the new tools.
Other thread that may be useful:
http://forum.weavertheme.com/discussion/11124/full-width-designs
http://forum.weavertheme.com/discussion/10344/index-for-the-weaver-xtreme-tips-and-tutorials-threads

At this point your site should mostly be there, exception for Per Page options and Shortcode related content.
As mentioned previously so far, you can switch back to Weaver II (Pro) and be back exactly where you were. The next steps will be final as they will implement changes in your pages / posts and content, that will no longer be compatible with Weaver II.
So if you are ready to finalize the switch go to the next step.

4) Pages. Posts. Content specific changes

• Go back to Tools > Weaver Converter > Convert Per Page and Per Post Settings section.
• First Click on “Generate Per Page/Post Pre Conversion report”. This will show you all that will be done, and you can see if some things won’t convert and what they are.
• Then Click “Convert Per Page/Post settings” to execute the conversion
• Now go through each page of your site and check if there are still things that need to be done like:
  • Adjusting the sidebar configuration, taking advantage of the new stacking modes that area available for mobile.
  • If you used Custom Fields check if they are using the proper/best HTML Insertion Area
  • Take advantage of the numerous new per page options.
  • If you have “Plus”, Pages now have a “per page style box”, so if you had page specific Custom CSS rule starting with .page-id-xxxx you could move these in their respective pages.

5) Shortcodes

• Shortcode content:
  In + Xtreme Plus > Xplus Save/Restore > Restore settings from your computer, browse to the wxplus file downloaded earlier and click “restore options from Specified file”.
• Activate the Weaver Theme Compatibility plugin. If you get messages indicating some shortcode cannot be made compatible, you will have to go and edit these manually

You may have to change their name like from  weaver_xxxx to just xxxx as well as their options if not identical in Xtreme and Weaver II.

• If you used the [weaver_show_posts] shortcode, You will need to use the Weaver Show posts plugin (used to be called ATW show posts) to create the new equivalents of your shortcodes. Weaver Show post gives you the same functionality plus more, with a much easier user Interface to configure what you need. If can also be combined with Weaver SHow slider to create post sliders.
  

6) Final Review

Once you have everything done, take the time to go through all your site pages examine the mobile behavior, and think if some of the new Xtreme features would actually allow you to do a better job than before.
If you have “Plus” one of the areas that you can improve, are the behavior of multiple widgets in widget areas. You can now define variable width for each widget and decide for a different layout on desktop, small tablets and phones. You can also equalize the widget height if you are using a widget background. (Check the tutorials index linked previously)

7) Backup

Last but not least, go to Main options > Save / Restore, Click Save Settings to make a copy in the database, and click Download All Settings to keep a local copy.
If you have “Plus”, go to + Xtreme Plus > Xplus Save/Restore page, and Click Download Save ALL Settings, to download a local copy of EVERYTHING…

NOTE: A user reported the  following issue http://forum.weavertheme.com/discussion/12539/tip-when-converting-from-weaver-ii-pro-to-xtreme-deactivate-wp-minify

WP Minify combines and compresses JS and CSS files to improve page load time.