Save Game Corruption (Again)

Yes, I'm using Unnamed's Stock AI Mod. But I had these problems in an earlier stock game.
In the last patch there was a fix which indicated there was a problem with save game corruption on a "huge" universe game, which I think is what I'm playing (can't actually remember what the size is).
The way it corrupts at a certain point in the game suggests that I'm hitting some sort of capacity limit. This is reinforced by having Autosaves work, but ordinary save games corrupt (for a while anyway - then both corrupt). A game saved during a turn will theoretically have more info in it (eg more stuff in the log and movement orders etc). But this could be a coincedence.

HD didn't look like it needed defragging, but I did it anyway. Will test it out over the next day or so to see if it helped. I'm about turn 130, and in a smaller universe than yours so it can't be the size (or at least not just the size).

Ok, so the game seems to be working again. The last few turns of play have resulted in no corrupt saved games yet. So the defrag might have helped.
Guess time will tell.