Thank you, however: "I want change tabs to be Ctrl+Shift+Pgdwn/Pgup"
I don't think that is possible.
Also, when I use Groupy with Display Fusion to move windows around, a lot of times it bugs out and I have to ungroup the windows before I can see them again.
I have forwarded your problem/question to Stardock Support Team for their assistance. Please keep an eye on this thread for any updates. We appreciate your feedback and patience.
Note: Please include more information on your system. As a guide refer here: https://support.stardock.com/space/SHC/1387954187/Contacting+Stardock+About+Groupy+Issues
Stardock Community Assistant