Thanks again for the detailed report, it really helped! I found a likely cause and made a test build with some fixes:
• Small sprite frames (bullets, effects) stored beyond 3 MB could be read from the wrong ROM bank by the DMA, giving random corrupted tiles on real hardware. They are now copied to RAM first.
• Enemies now enter one at a time instead of in bursts.
• The DMA budget per frame is lower on NTSC, which has a much shorter VBlank than PAL.
If you want to test it, here is the build (FULL edition, SSF mapper): https://drive.google.com/file/d/1v9d8kMRSrsd7yGT73rxzs53FA54LZdGq/view?usp=drive...
It would help a lot if you could try it on the same consoles and flashcarts as before, especially level 2 and 5-2 where the problem was most noticeable. Please let me know:
1. Whether the graphical errors are gone, reduced, or the same.
2. If anything new appears (slowdowns, missing animations).
3. The console model/region and the cart you used.
I can't test on real hardware (today) myself, so your feedback is the only way (today) to know if this worked. Thank you so much! 🐢
