Is this what you are looking for?
It's an introduction on how to use the peer variables commande inside a solid edge assembly to link two parts (inter-part association)
What I do for things like this:
I work compelatly in ordered
I create planes that represent the nominal dimensions of each "thing" in your case, doors.
Then I create sketches for each part starting with includes from the planes. Make shure all of the details are relative to the first included lines from the planes.
All assembly driven parts & sheet metal. They have to be created in context of the assembly. When you start each part, Turn off the parts planes and make sure only use includes from the Assembly planes
To keep track of the variables, Highlight each assembly plane with the variables open, that variable highlights. Rename the plane and the variable the same.
When complete, if you move one plane, everyting relative to it re-sizes.
Here is a Vid I did long about that was made to show now this realted to bend tables, but it shows the concept.
Is it possible to access assembly variables while editing a part in place? I use "Peer Variables" as you mentioned before. I can access other parts' variable lists by clicking their names at pathfinder but I can not reach assembly level variable table. Only way I can get it right is to close editing the part and turn back to top level assembly. That would be nice to reach assembly level variables from active part.