Diabol I think you should check out the "Duplicates in C64 DATs" thread in the member section, as far as I know we decided there to correctly identify the files that have been in the "Collection" DATs and not the other way around, so actually the Floppyshop Demos Collection should be renamed to the proper demos and then use something like:
Grazeys Zak Music Hacks Disk 01 (1993)(P.H.F)[Floppyshop 5446].st
as filename.
Anyway, read the thread again, as I don't recall everything about it right now.