A tip by user "Amiga68k" helped me to make some kind of work-around for OS3.2 by using the separate file solution and redirecting by *><, which seems to work in OS3.2 too. Unfortunately the ROM command issue still prevents making a "universal" solution, but two separate exes, one for OS3.1 and one for OS3.2 (and anything later than 3.1), should work for now.
Re-uploaded the archive to
Aminet and that contains the both exes.