As a Deluxe Music 2.0 user I ran into the same crashing issue.
I just wanted to add my observation.
I appears the crash when playing some of those "scores" that come with the program are happening because of the "instruments" assigned to the stave. Some of the included "scores" do not crash and they use different "instruments". The offending instruments are banging the hardware in a way that is a problem I assume.
Two solutions:
1) change the offending assigned instrument to another built in instrument that works.
2) assign Midi Instruments to the staves instead of built in Amiga sound instruments. If you have a Midi set up (which I do) this *seems* to fix any crashing and midi instruments through a synth will sound better than sampled Amiga instruments anyway.