When you both build the source drawing are you setting up the drawing for full design in that everything is setup and then placing it in a drawing that has another full design?
I have found that it is best to do a basic design in the source file. This should include the following:
Part List
Basic Style for structures & pipes
Then the drawing is shortcut into will need the following:
Final Style for what you want it to look like when you print
and that's about it. The part list, rules, etc... are not needed because they are set in the source drawing. All you will do is give yourself a headache when allowing the new drawing to mess with the objects as they come into the shortcut drawing.
All you should be doing is setting the view and label styles.
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