Mega Man II & IV MSU1 (infidelity) Krzysztof "MET" Słowikowski Guitar Playthroughs

looks like you just need to double-up the ROM data with a hex editor.

Long story short, the game's code erroneously jumps to a higher bank in the LoROM address space, but there is no data there. That's not saying his code is broken, but flash carts/emulators auto-mask off any address bigger than the original game should be using so if the bank doesn't initialize to the lower half of the address space then it glitches. The SNES Blaster doesn't have a big FPGA in there so it doesn't handle all addresses, so it can't do auto-masking.

I've tested it working on a SNES Blaster here, so just double-up the data in the ROM file and you'll be good to go.