"Patch 332 302 (gog-2) -> 332 (gog-3) 706 MB" is the patch, yet when installing it states "...needs 50MB space to install".

That is some funky compression ;)

Haha that's weird.
I've also noticed that the update installer is 706 MB and the full installer is 1 GB. But the update installed through GOG Galaxy is 1,6 GB. No clue why but there's probably a reason for that.

I guess when the world lost all electricity, something struck the installers &/or GOG client ;)

Never used the client though, so didn`t know about that.

I use both. Galaxy Client (beta) on my main pc and I save the installers for a smaller pc with very slow internet.