hmm, I think you only get a checksum error if you don’t change the pk3 name, then you’d both have the same file ‘supossedly’ but different values.
anyway most of the time I only change pk3 and bsp name, since the arena file is only used for the loading screen I think.
And then too many files in ETmain is also true, but this is not really something mappers can help, except not release too many small updates 