create a new layer at the top of your main timeline and drag your object to the stage. does it go to 0,0?
if not, do the same with a new layer on the timeline where you want to add your library object. does it go to 0,0?
if not, position your object where you want and drag that layer where you want.
delete the main timeline added layer if that's not needed.
On a new layer, it goes where I want if I drag the object in frame 1. But if I add a keyframe at frame 16320 and then drag an object to the stage, it goes to 0,0. This is true for both the new layer and the 35th layer I have been having problems with. Another weird thing is that when the object goes to 0,0 I can't create a motion tween.
flash pro only supports 16,000 frames per timeline. anything beyond frame 16,000 in any one timeline is problematic.
redo your setup so no timeline has more than 16,000 frames.
I didn't know that. Thanks for letting me know.