2Martin: Do you have llaecs.exe in mptstart.cmd? (or how it's called in ArcaOS, I don't know) If yes, please rem it out.
It can cause problems if VBoxService.exe is started via run=... statement in config.sys, and in some other cases. Or,
you can move VBoxService.exe to startup.cmd. This is a known problem of llaecs.exe. It interferes with PM programs
started from config.sys from run=... statement. Such programs are paused to load until PM is started. Otherwise, OS/2
may hang when a program tries to call PM API's. But llaecs.exe causes a glitch, so it seems, a PM program is not
paused loading until PM is started. So, better avoid to use llaecs.exe. It causes a lot of trouble.
PS: DId you read README? This problem is described there.
PPS: I looked into llaecs.exe, it's imported modules table contains pmshapi.dll. So, it is a PM program too. Maybe, the problem is because
it is started from a .CMD file, not directly as run=... so maybe, the problem should be fixed, if you move it to config.sys as a run=...