Yeah, it's weird, 0x26 + 0x10 doesn't seem to do much, aside from making the game run at about 3 FPS: the flashing is just as bad as without config, unless I also add either 0x27 or use 0x0F + 0x10 instead, but in that case it just works almost the same with 0x27 alone, i.e. makes flashes less prominent, but doesn't get rid of them completely.
In fact, because the game runs so much slower with 0x10 active, those flashes become even more noticeable than with a config with nothing more than 0x27 (such one usually looks almost comletely fixed).
Does PCSX2's div hack affect VU0 operations as well? Psdev wiki says that one of the modes for 0x12 is essentially 0x10, but for VU0 opcodes, so maybe that could help? I would try, but I'm not yet sure how to use that complex command properly…
Here's the memcard with all levels unlocked that I use with PCSX2, and I also included two savestates for both PAL and NTSC versions there:
https://gofile.io/d/6m3pYz
The level with that broken cutscene is called "Powers of Levitation". Unfortunately, the game doesn't allow saving mid-level, and the cutscene in question triggers at the very end, meaning that it's required to play the whole level from start to finish to see it. If you're not familiar with the game, the video I linked earlier should show how to beat it, but doing this every time sure gets annoying even when you know what to do. (
Thank you so much for trying to help me!