I always rename the default config (Config<1>) to "Base ". Which I use to make global changes, by unlocking all or unlocking the change refers to. Then when I make a new config (lest say config 1) I use the base as the template for the new config. Now depending on what the next config is I select either config1 or base as the template. Meaning the second (not counting base config) config can be almost like the first config expect for possible a line, circle, or some other feature diam or shape is different. The attach part file shows what I am talking about.
I have a port that each config has has two parts to it. The first part has a sketch use as a Boolean subtraction tool in the final assemble to create a attachment seat, The second part has the Boolean substation tool sketch suppressed. How I did this is I made a config call "Slide 1 BoolSubTool". I use the base config for this config. The I created the next config labeled "Slide 1 Assm" using the "Slide 1 BoolSubTool" as the template. I repeated this pattern for all the slides (60). Make a new Slide x BoolSubTool using Base as the template. Then make the Slide x Assm config using Slide x BoolSubTool as the template.
I hope this helps. Configurations are very very powerful tool.
RocketNut