Hi, I would like to offer my help with this, though my set-up might be considered 'suboptimal':
I have a PAL Dreamcast with Terraonion's MODE. I can already confirm, though, that 'Vampire Chronicle' and 'Sengoku Turb - Fanfan I Love me Dunce-doublentendre' (what a name) show the exact same issues as described by ufdm.
I can, however, also confirm that some NTSC games, like EGG, will just not run on my device due to it being PAL (despite MODE's region patching).
So, here's what I can do and provide:
- play NTSC ReDump verified game dumps on my PAL Dreamcast with SCART RGB cable on a 100 Hz CRT
- should issues arise, I would start them up again with a composite cable
- should the issue be solved, I will submit the game as likely having issues with RGB - should the issue persist it likely means the game has extra copy protection/region locking mechanisms (or just maybe some bug?) causing the issue on PAL devices
I will, of course, adjust MODE's settings to be as close to og hardware as possible (accurate GD timings and such) and first verify, if I can reproduce everything found here so far. Despite that, my results will still be 'uncertain' or 'MODE specific', due to my set-up.
Will you still accept my findings?