Can't get new theme working in Windows 8.1

[thx1200]

EDIT: I'm an idiot.  I forgot to reinstall the uxtheme mod after upgrading.  DOH!!!!!!!!!  Op, feel free to delete this post.

I recently upgraded to Windows 8.1 and I can't get any new theme to work.  I had no issues in Windows 8.  I'm using 1.5.5.6.

Here is what I'm doing.  Any idea what I'm missing?

1. Copy everything in C:\windows\resources\themes\aero\* to new folder C:\windows\resources\themes\mytheme1
2. Rename any file with Aero*.* to Mytheme1*.* (msstyle file and mui file)
3. Run WindowsStyleBuilder as admin
4. Open MyTheme1.msstyle
5. Make changes (for testing purposes I edited the bottom frame border image only and didn't do anything else yet)
6. Saved theme, including .theme file
7. Pressed "test" and got the "Error Testing MsStyles File" with message "There was an error applying the test MsStyles File, this usually signals an error in the Msstyles file."  Well, this is disappointing, but if I can apply it system wide, I'll make do.
8. Moved .theme file to c:\windows\resources\themes and made sure any appdata paths were changed to windows path (only one was wallpaper)
9. Applied theme in Windows... Nothing happens.  It just applies the default theme with no changes.  I can tell the custom theme is not being applied because the files are not locked.  I can still edit them, save over, and delete them.

What am I missing here?  Is there some trick to 8.1?  In Windows 8, I had no issues at all.