I had hoped it would be perfect, but it seems we at least made some progress.
Maybe when you run with multimon for the first time, the monitor it chooses by default (which should be the OS' default monitor) for some reason hangs Spine. When you close Spine (the launcher or editor) it remembers the monitor it was on, so it can put the window there next run. So when you ran with a single monitor, then enabled multimon, then closed Spine, it remembered the monitor and subsequent runs should use the same monitor.
Can you please try running Spine with multimon, then move the window (the launcher window should be sufficient) to the other monitor, close Spine (normally, not via end task), then run it again? My theory is that if Spine tries to start on one of your monitors it fails for some reason but the other monitor is OK.
When you uninstall, your Spine user folder should be deleted and that's where it stores the monitor it will start on. Specifically, it's in the <userhome>/Spine/settings/start-1.json file. Note the monitor number Spine stores is not necessarily the same numbers that the OS gives to the displays. Anyway, just deleting that file will reset Spine's monitor choice like a fresh installation. If Spine can open on either monitor in the test described in the previous paragraph, then the next thing to try is deleting this file (or the whole <userhome>/Spine folder). If it also runs after that then everything should be working!
The Spine installer shouldn't leave shortcuts after uninstallation. At least, I see the installer code that should delete them and it looks right. We'll check it to be sure.
When you run 3.8.99 it takes a little longer to go from the launcher to the editor window appearing. The monitor choosing happens when the launcher is shown, so if the launcher can show then the editor should also.
Great, glad you'll join the Spine community! 🙂
