I installed this game with the off-line installer and played base game up to the Hart Secul campaign on Naboo. Then I got stuck and left it for a while. I came back and now none of those saves will load. After much poking, I noticed something. If I try and start a new game, it saves with .gax extension. The old all saved with the .ga1 extension. Now, I didn't change anything. So how did the game decide it needed a different extension, or how did the old saves get saved to a new unusable extension? That is a lot of hours lost if there is no way to undo it.

I did put in a support ticket, but I also thought I'd try here, in case someone else had ever encountered this.
I have also checked the complete backup I had on an external hard drive and that is doing it too!