Your comments

Don't worry, the fact that you guys haven't forgotten about this proves your teams dedication which is awesome. When i played the game it was real hectic, getting attacked from both sides, loading reloading. Tried different approaches, with finally sacrificing one stone to hold on, maybe during all of that something glitched out. Thank you anyway for your efforts.

"From memory, saving and reloading used to cause this bug. I thought that it had been fixed though."

- Well since i played on master difficulty i did reload a number of times, so that might have caused it?

 "The AI actually plays badly in level 1 because it does not try to finish off players"

- Oh the AI on master is an unending tide :) , so no stalemate there. (I played as Volta and my opponents did everything to annihilate me so the only thing i found that works is to sacrifice one shard and fortify the other, hence the bug i reported. I finally managed to overtake after a while but no victory)

Just a small bump so you don't forget

Oh, and Happy New Year :D

ok take your time, if i'm gonna try master difficulty for the rest of the Undergames it should work properly. :)

Have you had a chance to look into this?

Also my question remains 

Do i need to have both shards intact to win a game in the Undergames?

Ok here is a save after the destruction of the shard and a log file, i had a manual save as well just before my final assault but i can't seem to find it. I'm on the GoG version.

1 group stage volcansnow_20181008014438.meta
1 group stage volcansnow_20181008014438

Ok I'll upload saves before and after destroying the final shard.

About the data written, i don't mean installing the game or the game size. No, I'm referring to starting new missions, loading saves etc. After exiting a normal game session where i've played a couple of games or loaded saves i noticed the data write in a monitor program i use to monitor SSD usage. I guess it's the engine itself unpacking data in the background while the game is active.