Thanks for the pointer on the Rotax issue. For now, you can work around it easily. Change your engine type to "OTHER", go into RPM setup, turn off the units, then change the engine type back to ROTAX. The units will stay off when you do this.
I was hesitant in doing that initially, as some time ago I changed the oil temp name from 'OIL' to 'OIL T'. That resulted in the restricted RPM green band staying restricted. Presumably the oil temp was no longer recognised to trigger the full green arc at 50 degC oil temp.