Cubic scale keys:
Yeah this is tricky i'm not exactly sure what's causing this now, i used to think it was regional settings...but doesnt work for everyone. Try switching your keyboard to english when you export your file from XSI.
As for your friend's problem, he should always apply a reset xform before doing the weights. This has caused many problems to modders, it's a problem related to max's tools. To reset xforms, check the first part of this tutorial:
-before exporting the scene, select the "mesh_root" object from your scene and delete it.
In Assimilate check "Keep motion bone" and "make it's own skeleton" change the path to "models/players/_humanoid/"the name of your new animation" dont name it _humanoid.gla!!!! you can also change the path so it points to your character dir (just make sure you remove c: ) Next go to the "frames target" option (press + on the folder...) hit clear where it says ROOT do not change anything else.