I myself do not have a Powerpak, so I do not really know the details, but it appears that the Powerpak has issues with Satellaview ROM headers, even for games that could normally boot on their own on real hardware.
And here, is a visual comparison to give a better idea of what I mean:
In this specific example, the F-Zero ROMs are otherwise pretty much the same game – except that with that Satellaview header, the bottom one will not boot on a Powerpak. Also, as a reminder to mention, most Satellaview ROMs have Shift_JIS Kana headers instead of ASCII English headers. (F-ZERO appears to be an exception.)
This picture should also give a good example of what you’d want to change for a ROM to boot on the Powerpak – in particular most of xFD0-xFDF. The most important thing, if I recall right, is replacing the Satellaview checksum with a standard SNES Checksum.
Hopefully this is of help to you Powerpak users.
(NOTE: This will -not- work on every game. Don’t be surprised if a Soundlink game or a magazine reliant on BS-X Fonts fails on this.)