Drum Track Midi Export to GB not working

I tried exporting a song in midi format and importing it into Garage Band so I can record a part and ran into some problems with the drum track. I was exporting the song Blue In Green, which is a 60bpm track with brushes and very little going on in the drum track. I dragged the midi file into GB and everything parsed correctly to separate tracks. The problem is the drums notes are incompatible with GB. I used the Jazz Kit in GB and got tom hits where there should have been snare brush strokes. The other notes were wrong too. I tried transposing the notes but I couldn't make it to work.

I assume IRB exports as General Midi and GB's kits are laid out that way as well.

Any suggestions on how to get this to work?

I also realised this problem with GB. So I imported the IRB midifile Finale PrintMusic. The result was a little bit better but there were still wrong instruments in the drumkit. So it seems that different software vendors use different drumkit layouts. I would be very happy if somebody has an idea how to solve or workarond the prob.

You would think the mapping would match GB. The first thing someone is going to do with IRB is export to GB when using the OS X version so they can record themselves with an IRB backing track. I thought General Midi was supposed take care of this kind of interoperability.

This kind of thing is why I avoid Midi like the plague. Hopefully the vendor picks up on this post.

In iReal b I made a custom drum mapping.
For example the brush has different sounds on the up and down strokes to better mimic the real sound of drums.GB's drum kits don't have that many sounds so it's not going to be compatible.
I can't give specific mappings because they are different for each style so it would be very time consuming and still would not work.
When I first made iReal b, the tracks weren't meant to be exported to midi, that's a feature I added later and most people use for the piano accompaniments and bass lines.

Massimo Biolcati.