Hello,
Sorry to hear you are having issues. But, please we need more details.

1. Windows full version and OS Build number, please use Winver.exe
2. Start11 full version numbers.
3. What is not customizing? Elaborate more please.

Thank you.
Basj,
Stardock Community Assistant.

Maybe this guide will help you on how to post your issue: https://support.stardock.com/space/SHC/1387003915/Contacting+Stardock+About+Start+Product+Issues

Thank you,

Basj,
Stardock Community Assistant

I can not help until you give us requested information.

Add require information

1. Windowblinds full version numbers.
2. Screenshot showing the issue.
3. Issue happen with any Windowblinds theme?

Thank you,

Basj,
Stardock Community Assistant

Do you have Stardock Start11 installed? If not, you will need Start11 to get Start menu be skin. If you do have Start11 installed, we need to know your Start11 full version number.

Thank you,

Basj,
Stardock Community Assistant