Thanks for the reply! Both drawiings were created from the same template and I've double checked that each have the same styles available. I've also tried to making a copy of the source drawing, deleting everything from the copy and then adding the shortcut from the original source drawing into the copy, and I still get the same result. We have a number of styles for various grates, headwall sizes, etc., and I can manually update the styles, but obviusly that is not how the program should work.
On a somewhat related topic, when you create the shortcut reference, why does it have to ask what part list to use? Shoudn't it just use what has already been defined in the source drawing?