About the "same game different publisher" thing I was talking earlier, this is a real nice example, when the tool tells you "here look this is the same game so all should have same name" (for example):
Dig Dug (1982)(Atari)(US)(proto).xex
Dig Dug (1982)(Atari)(US).rom
Dig Dug (1983)(Atari)(US).rom
Dig Dug (1984)(Datasoft)(US).atx
Dig Dug (1985)(U.S. Gold)(GB).cas
I don't know if you have to deal with such weird stuff in C64 too but it can be really complicated and if you have a DAT that was made years ago and have a game like this with only "Atari" as publisher it can be very complicated to sort stuff out and name it all good.