[se5a]

This is SEV right?

regardless, it's not the shipset causing the problem.
your player needs to make sure he's got the same version of the mod files. he should redownload and re-install them

I've never heard of shipsets crashing the game.
if PBW does not have the shipset, when it processes (or if you don't have it when you process the first turn) it will permanently reset the shipset to one it does have.
the only problem you may get with a custom shipset is that the shipset creator didn't set up firing arcs properly, and the ship may only be able to fire in one direction, possibly making battles unfair for that player. Aaron has finally fixed this problem in 1.47 - we just have to wait for geo to install it on PBW.