then it works fine. When I double-click the app, on the other hand, it immediately closes without displaying any GUI. I tried getting some logs from Console.app but after looking at the source code I see you just use printf everywhere so that's not going to work. I would normally be happy with just running it from the Terminal but I can't figure out how to create hard disk images or eject/change floppies on the running system, making it difficult to do anything other than playing around in a single bootable floppy environment.
Do you use the new BasiliskII GUI beta? It is not notarized, so to launch it the first time you will need to use the right-click (or control-click) method.