Clarification for "Best Practice for Configurations with External References"

Hello,

I'm new to the Configurations/Design Tables features of SolidWorks, but I decided to experiment with these features as they seem like they could be very useful.

Context

I am creating a unit that contains a weldments frame, sheet metal flooring, sheet metal counter tops, siding and doors, and a serving shelf (which contains a sheet metal top, support beams, and glass.) I started by designing the base frame with a design table containing 4 global variable references and 4 dimension references. The dimension references are functions of the global variables (for example: "weld_width = cart_width - 1") that are calculated within Excel (rather than SolidWorks's Equation property manager.) See the "Base_Frame" and the "Base_Frame-Design_Table" pictures for reference.

I then created an assembly, inserted the base frame, and inserted a design table so that I can view the configurations that I created within the Base Frame part file. I then created walls and doors, a floor, a counter top (all via Insert Components > New Part,) and a serving shelf (via Insert Components > New Assembly) within context of the assembly.) The new parts I created are "Fixed" and have external references to the base frame and each other. The Serving Shelf sub-assembly is constrained with a Lock mate while containing features with external references. Images of the assembly (with the walls hidden,) along with the assembly's design table and feature manager have been attached to this post for reference.

With this set up if I switched my configuration, the rest of the assembly would update with it (though I usually need to press "Rebuild" afterwords,) which is good!

My question is regards to the following SolidWorks Help article:
"Best Practice for Configurations with External References"

http://help.solidworks.com/2015/English/SolidWorks/sldworks/HID_EXTERN_REFS_MSG_WARNING_HELP.htm?id=edc2084c239f48eaa492d2a443002095#Pg0

The article suggests against using the "n:1 Relationship" method, which is what I've seemed to use. Therefore I'm trying to implement their solution, that is, trying to create a corresponding configuration in each part. The problem is the external references within my parts are more complicated than the "Height + 20" relation within the Help's example. How would I implement their solution within my assembly?

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