No worries, Jan. I hope you were able to resolve the spam issue for good.
I had also posted my question in the P96 thread on EAB @ http://eab.abime.net/showpost.php?p=1480807&postcount=126
I installed P96 3.0.2 on AmiKit XE. When I try screen dragging with ChaosPro, I am able to drag the screen and see Workbench behind it. However, navigation with the mouse is pretty much broken. For instance, when I move the mouse up to Workbench, even though the cursor is still visible on the ChaosPro screen, mouse buttons are registered on Workbench. I can only navigate on Workbench by blindly clicking on random spots. That said, once I reach to ChaosPro window by trial-and-error, I can either drag the screen up or close the program without any issue.
I tried the same with Workbench 3.X that came with Amiga Forever 9 - I replaced the stable WinUAE with Beta 19 and ensured 32-bit version is launched by choosing "Play with WinUAE (32-Bit)".
I was able to drag the ChaosPro screen and the cursor was visible on Workbench when I moved the mouse up. However, I encountered another issue this time - the cursor was invisible on the lower screen. I had to click blindly to find the right spots. Also, random horizontal bars started to appear in the screen below and there was even a second mouse cursor left-over - see the screenshot -http://eab.abime.net/attachment.php?attachmentid=71796&d=1620079043
In short, screen dragging didn't work properly in either AmiKit or Workbench 3.X; that is why I believe there is an issue with the new P96 UAE driver (also pointed out by Thomas). However, as screen dragging exhibits different behaviors under AmiKit and Workbench 3.X, can you please give this a try when you get the chance? I will be happy to report any of your findings on EAB.
Below is a breakdown of my setup:
WinUAE 4.9 Beta 19 (also tried beta 3, 16, 17, and 18)
Workbench 3.X and Kickstart v3.1 (amiga-os-310-a1200.rom) from Amiga Forever 9
AmiKit XE 11.4.2 (default configuration - attached)
Windows 10 20H2
GeForce RTX 2070 Super (tried drivers 466.11 and 466.27)