a bug with models and the WE

so ive a fairly new moddeler, and iveused oinker quite a bit, gmax moderatly, and now 3dstudio embarking.

so depending on what im wanting to accomplish ill use whatever program that i can achience my goal easiest. and sometimes when editing various models and pasting certain parts together, when placed in the world editor, they will show up fine and everything, but i cant move them. i can not select them by clicking them, i must make a selection box to select them. and to move them i must also have a non-bugged model in the selection box and move the non bugged which moves the bugged one also in turn (because they were both selected in the selection box). it isnt a big problem, it just forces me to make a temp unit, move the bugged unit, and delete the temp unit. any ideas?????? i know when looking in the mdl parts of theses files there is a lot of wrong info (but it still loads/works fine in game, i jsut cant move them). what i mean by wrong info is if i pasted a part from an object that had an emitter, the new model which doesnt have an emitter will say in the mdl it has one. ive tried editing them to their most basic forms from looking at other mdl files that i know work, but no such luck.... any ideas would be GREAT! thanks-