Interesting, my testing machine was a PAL A1200 with a TF1230 with the game installed on the CF card.
Is your Amiga PAL or NTSC? (I’m not sure that it should make a difference, but if we can figure out how our systems differ, maybe it will give me an idea of what the issue is) How much chip RAM do you have free when you start the game? NEONnoir is pretty hungry and I believe it can peek at over 1MB. Is it possible that you have some utilities that are eating into it?