Yes You Can! - Include Elements in Linked Files in Schedules!

This is a recurring theme, "I've got more than one project file linked together but I want a single schedule of...doors...or sheets. Can I do that?" Yes, and it is EASY!

Just edit your schedule and check ONE box! See below...

Touched on a related topic in THIS POST regarding including other trades drawings in your drawing list. I mention three methods but there is also a fourth, use a Schedule Key but hide the key value column. This approach does mean you have to enter the information too but a schedule key has all the same formatting features/restrictions as a regular drawing list.