Last time the save corrupted, I was about an hour into it. I turned off the game and went to bed. Today, the save was ruined and I had to start over. And that was from me saving and quitting normally. What am I supposed to do, quit and make another backup every ten minutes?
...
This time I waited until he specifically told me to get the chest, and it still contained an invalid item. Bugfixing is still required.
...
Something this game could use quite badly: an actual set of options for video! There's so many glows and particle effects going on, especially in the forested areas, that it's eating into my already-poor framerate. I'd like to be able to turn some of them off, like the butterflies that seemingly nest all over the place in groups many dozens large.
If it's a CTD on loading your save, certain character customization options do that. (I managed to consistently crash it with a green beret, dark green tattered cloak, beady eyes.) Opening the save in a basic text editor and erasing the text on a line that ends in 'E' resets your appearance so, if it's the same bug, you can get around it that way. (It's the 5th line or thereabouts; already been reported and acknowledged on the official forums.)
It doesn't change anything; just an invalid item name. (Already been reported and acknowledged on the official forums.)
Have you tried disabling some of the spell effects by talking to the NPC on the 3rd floor, above the wand guy?