Product listing in centerbox clicking on Top-Categories

Hello, I've the following scenario:

topcat1
-Subcat1
-Sucat2
-Subcat3

topcat2
-Subcat1
-Sucat2
-Subcat3

topcat3
-Subcat1
-Sucat2
-Subcat3

Clicking on any topcat* the user have to see the product listing sum of the related Subcat1+Subcat2+Subcat3.

I've used the hideCategory mod (a little modified for my goal) to create an hidden subcategory (hidden to category menu) named "summary" in each cat*, then I linked the whole subcats to "summary".
The next (and final, I suppose) step to let the trick working is to modify or change the url get variable when I click on a topcat.
Supposing that cat1 has the get variable cPath=12 and the hidden subcat summary has cPath=20, is there a way to substitute it without a frustrating change of the code?

Thank you in advance, :smile:
S.

Sorry, there's no way to substitute one category for another without tweaking code.

Thanks for your reply Kuroi! I'm searching for a better solution.

S.