Just noticed this problem today.
When clicking on the Download link for a Windowblinds skin, SP2 pops up a window asking if you wish to Open or Save the file. Also, the file has been changed from the familiar .wba extension to a .zip extension.
If you choose to Open the file then Explorer opens the file as a .zip showing all the contents of the file. However, the convenient instant download and install does not happen.
If you choose to Save the file then the file is downloaded and saved to a location determined by you on your hard drive. However, it is saved as a .zip file, not a .wba file.
For whatever reason SP2 keeps identifying .wba files as .zip files on the WC website and worst, when saving them it converts the .wba extension to .zip.
Once the file is saved on your hard drive as a .zip, the only way to install it is to use the Add button under Display Properties/Appearance tab.
P.S.
When using Stardock Central to download WindowBlinds files the .wba extension is preserved, and will install automatically if you choose to.
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