... You could try telling Audition you don't have any effects folders, and see what happens. Long shot....!
I thought this was quite an amusing idea, so I tried it. I took out any VST folders, and then AA3 proceeds to refresh the DX plugs .. stops at DX: C (not a clue what this refers to) .. and crashes again. Hopeless. I'm going to try AA3 again when I re-install the OS, but until then it's on with my work in AA2.