When I do this, it has that old problem where it breaks down the C the I and the B to where you cant edit just one.  Could this be looked into please?

I was wondering this just the other day. 
Through some testing I figured out that if you set your collection type to either "For Sale" or "For Trade" then it will give you the option of setting a quantity to each C/I/B value.

For my setup I kept my current collections as "Generic Collection" and made a "For Trade" collection to handle all my duplicates.

Hope that helps.
 

Mines not a duplicate though, its a variant.  It can be fixed, as Dain has done it many times in the past, but he just needs to be made aware of it.

Go to "Find & Add", enter "battlefront" for the keywords, choose ps2 for platform, choose the collection you want to add it to, but you need to uncheck the "Only show missing games". You can then add as many copies of the same game to your collection as you want.