Assemblies, Configurations, Equations & Design Tables

Ok, here's my problem,

I built a final assembly, a food tray deleviry cart for use in a
hospital. Just about about all of the parts have some type of an
equation in them so that I can control the size of the cart
parametrically. I'm controlling the size and shape with a "3D" sketch
in the final assembly. There are 3 dimensions and 1 pattern in the 3D
sketch. 1-for width of the tray size, 2-for the tray depth, 3-for
shelf spacing, 4-fornumber of shelves. The last one I used a pattern
to control how many shelves I would need. With everything set up and
working, I go to the 3D sketch, change any of the values or all of
them, do a full re-build and the cart changes with no problems.

After that was done and working, I needed to make 2 more carts. One
cart has 1 more shelf and the other has 1 less. I figured I would use
configurations for the parts since the only thing changing in this
case is the height of the cart, by 1 shelf. I created configurations
for all of the parts that would change height (side panels, back
panels, inside shelf frame, etc.). Then I created assembly
configurations that would use the appropriate configurations of each
part for each cart.

After getting everything set-up, I go to the 3D sketch in the final
assembly and change the pattern value and also select the option "For
This Configuration Only". Now when I change the value, with it set for
this configuration only, the cart doesn't want to change size. If I
change it back to "All onfigurations", it works fine again.

Any suggestions?

Thanks in advance,
Richard