Thanks Bwian. Your advices will prevent me to spend time in this question.

This horse animation was required for a type of chariot, but now the problem is the chariot itself. The model looks nice in 3ds max, but when I try to put it in game I cannot see the chariot.

I see only the horses, the harnesses, the pole (in wrong position, but it is visible), the wheels and the crew. It is not the alpha channel, as it is correct.

I have also problems with the different values in descr_mount and export_descr_unit. The chariot is much larger than the usual ones, and there is some mistake. The formation of the three chariots is not correct (they are not in one line) and when loosing or packing the formation, they move in a strange way. Finally if I give them the order of walk, the game CTD.

Any idea?