xsi5 : key multiple objects script problems

This is driving me crazy. Sometimes this works, sometimes it doesn't, but I can't seem to figure out why. Most of the problems seem to ocucr when I run this over objects that have a key on them (updating keyframes) or inbetween key frames. If I move the timeline past the last keyframe and run this is seems to run fine, but in the other situations, sometimes the keys are not in the correct places or sometimes (when updating keys) only the position of one or two objects are saved and the rest move back to the original position.

All the objects do have marking sets and I have tried various other ways of setting keys (SaveKeyOnMarkedKeyable, etc.), but nothing seems to be working. I'm currently using 5.1.

Any help is really appreciated.

Edit: If I comment out the SaveKey and run the script and then key with the K key, everything seems to work as expected. Is there a different way I should be saving the keys?


DeselectAll
SelectObj "Rigged_Textured_Final-3.R_Foot_ctrl", , True

AddToSelection "Rigged_Textured_Final-3.L_Foot_ctrl", , True

AddToSelection "Rigged_Textured_Final-3.Baby_Cog_Control", , True

AddToSelection "Rigged_Textured_Final-3.Upperbody_Control", , True

AddToSelection "Rigged_Textured_Final-3.Chest_Control", , True

SetMarking "MarkingSet"

SaveKey