Help: Saved games have become corrupt after graphics driver update

[Morea]

Hey all,

I've happily been playing Rimworld version 0.9.722 (released on Feb 18) for quite some time. Today I installed a driver update, and my old save games won't properly work anymore.

Here is the screenshot: http://i.imgur.com/VoqJ1nY.jpg

The save games can be opened, but none of the textures will load and the game is essentially blank apart from the interface (see screenshot). The error screen pops up immediately and starts listing "Object reference not set to an instance or an object", racking up into the thousands. Note that when I tried starting a new colony, everything worked fine.

Here's a link to the output_log.txt from my Rimworld data folder: https://www.scribd.com/doc/261946581/Output-Log

I am running Windows 8.1 on a very decent gaming notebook. The update for my built-in graphics card by NVIDIA GeForce Experience has been pending for about ten days prior to today.

Now there are various things I can try to get my old save games to work again.

- I could undo the install of the graphics driver using Windows' restore function.
- I could export the save games, reinstall Rimworld, place them back in the folder and hope they work.
- I could try looking into the settings of my graphics driver and see if I can fix it.
- I could give up on the old saves and just start over.
- ?

Tips, suggestions, questions for additional information, solutions; it's all welcome.

Thanks a load in advance!
Morea