I don’t know if anyone has tried this before or not, but I did, and it didn’t go so well, so I’m hoping that Blizzard or someone can give me a hand with troubleshooting.
After upgrading to Catalina, I decided to setup a Mojave VM for my 32-bit Mac games, running in my copy of Parallels. It’s worked fine so far, except with Diablo II. When I start the game, the screen goes black and stays that way until I hit Enter, then the program just exits. If I click on the black screen instead, I get the little error ping. Hitting Enter exits the game whether I click or not.
I have wondered if this could be a resolution problem, or even a driver/hardware compatibility problem. This is happening on a new 16" MBP with a 3K display and Radeon 5500 video card. I have tried running the VM at 1024x768 and other resolutions, all to no avail.
So where can I find logs that might help? Or what else can I do to further troubleshoot this?
EDIT: Solved my own problem - or at least found the root of it. Neither Parallels nor Fusion virtualizes 3d accelerators for macOS guests, just Windows. Grrrr…
I have submitted a feature request with Parallels; we’ll see how that goes.