About the second mission addition with Samus, will it work even if I started a second playthrough as Dawn because I last saved back at the ship after going through the SMB easter egg area and I have all my upgrades from the first playthrough?
It would most likely require completing the game with version 1.20.
Didn't encounter that bug. @Snarf; Is this emulator specific? Or am I just lucky?
It's an uncommon bug caused by uninitialized RAM. Likelihood of it occurring depends on emulator, but doesn't seem to be an issue on most. Possible for it to happen on actual hardware depending on the initial state of memory.
It seems very likely to be an issue with the PowerPak itself.
We also don't know if he patched correct rom or not. So it also can be just his rom issue
That sort of VRAM corruption is not likely to be the fault of the PowerPak, so I'd hate to bother BunnyBoy, even though he's been helpful in the past. It's possible the wrong ROM was patched; it's possible it's an uninitialized memory bug. More info would be helpful in understanding what's happening (ideally, name and version of the emu or flash cart and a copy of the SAV file).