Bug in max biped exporter

[Mikachu]

I have made a walk animation from the standard 'footsteps' mode in 3dsmax. It exports fine, but if I set the active segment to 45->75 (which corresponds to my loop) instead of 0->100 in 3ds, and then export, it is not exported correctly (the arms are rotated around the wrong axe).
It has nothing to do with the segment I choose in the exporter, it works fine if I do 0->100 or 45->75.

Does anyone know a way of debugging this?

[Crashy]

Same thing with the normal skeletton. But that's not really a problem