about "scrolling stars", I think the Test Program alternates main & sub screen to give a sort of scrolling effect. my bet is that we fail to properly emulate some addsub corner case, but my first attempt to fix it, failed. I will try again once I've finished a few other things I wanted to clean up.

from the top of your head, can you remember:

* any game which uses OPT actively in easy to spot places, in addition to SNES Test Program (for the Mario screen above)? I know Puzzle Bobble uses Mode 4, but I was not able to find an occurrence of opt valid bit written

* any game which uses pseudo hires?

* any game which uses mosaic in Mode 5/6?

I think my current code still has some problem with the cases above, but I would need some separate test case for each of them, in order to test fixes...