> I was wondering if there is any reason that I might need to hold onto old
> versions of ClrMamePro.

No.


> Are new versions of ClrMamePro backwards compatible with _all_ old versions of
> mame?

Yes. The direct data import from a mame executable can be used since MAME 34b1 (iirc). Before that you have to create a datfile manually. Very old versions don't use crc32. Instead they use some own hashroutine. I don't support that anymore.



To sum it: There is no reason to keep old versions of ClrMamePro...and there is no reason to keep old MAME versions either.

Roman Scherzer
ClrMamePro