The Problem:
Auto-installing Skin/Theme files are downloaded as zip files.
The Cause:
SP2 appears to be common factor, but some people report no change after SP2.
The Solution:
Step 1. File extension must not be hidden. If you're unsure what that means, open Control Panel > Folder Options > View tab > "Hide extensions for known file types" should be un-checked.
Step 2. Right-click the file and select Rename. Change the zip part of the name to the proper extension. Example skin1.zip = skin1.wba (for a WindowBlind skin)
If you get a warning about changing the extention, click OK
Step 3. Double-click the renamed file.
Be aware that skins and themes are sometimes uploaded in the zip format for various reasons...... always check the zip, before you rename.
DesktopX Themes = .dxtheme
DesktopX Objects = .dxpack
WindowBlinds = .wba
LogonStudio = .logonxp
BootSkin = .bootskin
CursorXP = .CurXPTheme
IconPackager = .ip