The game hangs up at "Processing diplomatic exchanges..."
Sometimes it happens at "calculating planetary production", but i have no such savegame.

Hey Quant2m, welcome to the forums!

The game hanging like this is a very well known problem, but Mike (The developer) is working on a major programming update that *may* fix it.

Thanks for attaching your save game, i'll make sure Mike knows it is here.

Oh, ok. I didn't know that.
I found only one post about that problem on a quick search.
Anyway, hope it helps.
bye

It's actually been posted about on the forums for almost two years now; i've been around here for more than four years so i've gotten to know these things.

The freeze bug has been around since the very first incarnations of Supremacy, but the cause has eluded Mike for that whole time. He's currently refactoring the whole Supremacy client, which is a major undertaking, but *may* finally fix the bug. With any luck it'll fix a couple of other elusive but lesser-known bugs too. Another positive thing is that it may also improve turn-processing times, so it's going to be a highly anticipated update.