I don't know how else to explain this, I've noticed single frames here and there during transitions where graphics are corrupted. I figure these happen when objects are being unloaded from memory. I do not know if this also happens on actual hardware, I can only imagine it doesn't. I also do not know if this has been posted already, sincere apologies if it was. I'm hoping this find could lead to a fix and improvements to the emulator. I've also noticed the Power Edition displaying Asian characters on the track/car/transition selection when using "Export" for country (I can post screens if requested), perhaps this is the same issue.
Thanks