Hey just to see if I'm having the same problem Does it lock up the entire computer or crash to desktop I have the entire game brick my computer and just recently had it crash on the splash screen shutting the entire computer off.

Search forums/google. Many fixes are known for 10+ years to combat instabilities, try them until one helps. There is no silver bullet. E.g. try disable steam overlay, verify game files, set win xp compatibility on exe files + run as admin rights on those also, etc. etc.

Sadly the devs refuse to maintain a FAQ here so it is up to you to keep looking.

Unfortunately the solution is to never do ground battles. Ive tried everything under the sun I can find and nothing has helped. Only doing space battles I get a 1 in 10 crash so the mod is at least playable now. Ground battles still crash often and various planets are guaranteed crash for me

That is sad to hear, when I last played 3.3 (before the 64-bit update) it was very stable, only a few of such crashes occured during 100+ turns and those were typically after running the game for several hours and/or in huuge space battles (yes OP Hapan doom stacks I am looking at you!). I don't recall having any ground crash issues at all in this mod lately (in some others you have those, often hero related).

For most people this is stable, but yes I had to use some of the tweaks I mentioned above to achieve that. I vaguely remember applying some other tweaks to the game a couple of years ago (memory tweaks in the registry?) that may have helped that I found on google.

Also I save at least once every round but never save close to end/start of cycle so never had saves corrupted and for the few other game breaking bugs (e.g freeze on galactiv map when ai vs ai battle goes into eternal loop or in battle when you battle an ai hero that becomes invincible during battle) I found a way to work around.