Very odd.

So in hyperterminal, can you control the player by typing commands? For instance, can you press N <enter> and it will go to the next track?

If you can do that, but logoedit doesn't communicate properly with the player at such an early stage in the kernel image process, then I'm rather stumped. It should Just Work.

I believe that I and others have suggested as many as three times now, in two different threads, to try doing the work on a friend's PC, i.e., a computer with a different serial port. Did you ever get around to trying that?