Purely a guess. Since the owners manual has the 8,16,&30 all encompassing in it since it's the same series, I would guess that as long as any scene isn't larger than the one you're trying to use it on, like 16 to 8, or 30 to 16, etc., or even the reverse going up instead, logically in my mind I think it should be compatible. The 30 has more features so I assume it would just ignore those.
I did a search for the word "Scene" in the manual, and this copy/paste below was near the end of the search, so it sort of supports my theory, but still not 100%.
" IMPORTANT!: It is possible to recall TouchMix-8 and TouchMix-16 scenes on a TouchMix-30 Pro. Of course the TouchMix-30 Pro has far more inputs and outputs. These excess inputs and outputs will be set to factory default values. "
