It sounds like you have either the PPC version of SDL and are trying to run the intel version of EUAE or you have the intel version of SDL and are trying to run the PPC version of EUAE... Either way, you need to make sure you have the intel (or universal binary) version of both.
But how would that work? For any PPC codee to work Rosetta would have to be installed. Apart from that any PPC code ran on the x86 would surley be emulated and endians reversed to account. If the SDL lib was using the wrong endian everywhere the whole thing would crash!
But I can see how a BGRA framebuffer would be messed up by an ARGB image.
