there is nothing wrong with being thick...
this should help, ...
its not a cat in the normal sense, instead you map your own "text boxes" onto the category and display them where ever you want.
I use a single entry cat for the "big" photo and let that handle drill downs/scrolling etc.
I have it set so if you click on one of the other photos it jumps to it (i use xDatabase to move the required number of items).
You also do nice "cover wall" types screens in the same way -