I did encounter some weird graphical issues when upgrading from a previous version during test. I reported this to the dev.
If you have issues, I recommend:
1. Make a backup of TValle Document folder
2. Delete the TValle Document folder
3. Install the game into a NEW folder
4. Play the game and make sure it is fine
5. If the game is fine, install mods that have been updated to support this release
In regards to the in-game lighting being too dark, this was reported several times during alpha. The entire scene lighting uses a different model (probe volumes) and I suspect things will need to be tuned to look best on all hardware. On my test systems, I usually bump the lights to 55-60 to be playable.
-T-