Hello,
Sorry to hear you are having issues. First, Please try, uninstall Start11, reboot immediately (important), download latest version available in your account product download page: https://store.stardock.com/myaccount/products. Install it, reboot immediately again. Retest it and report back.

If the issue still appear need more information on your system.

1. Start11 full version number.
2. What application show up (the small tab appear on the left) when you move your mouse?
3. What application is running to animate your wallpaper?
4. Do you have any other application running which also control how your taskbar work?

Thank you,
Basj,
Stardock Community Assistant.