I'm not sure what the problem is with your game, and I think it is fair to consider a possible hardware or 3rd-party software problem on your end. Reasoning: we have sold thousands of copies of Book II, and there are relatively very, very few complaints of saved game corruptions. Certainly we will always look at ways to improve the stability and reliability of our game-save protocol, but in reality there are only a couple commands used to read and write game data; these functions either work or they don't. When 99.8% of people never have a problem with saving their game, we have to consider what is going on with the 0.2% who report problems.
One suggestion that we have provided to people is for them to go in and delete .map files to reset specific zones. This is a very dangerous suggestion and we do not recommend it unless there is no other option. Deleting the wrong files could be catastrophic and ruin multiple save positions.
When deleting .map files, we also suggest removing two other files associated with the map: the .ent file and the .opq file. These 3 files (.map / .ent / .opq) should always be deleted together to properly and fully reset the map.
Likewise, if anyone tries to manually alter data inside a saved game file, it will very likely result in unrecoverable corruption. This is why we do not support or recommend any 3rd-party character or map editor.
In the end, we will always work with customers to improve the process and help them when problems arise. In your case @theanonymy, I would recommend making a copy of your saved game folders (such as copying it to your desktop), then remove the entire saved-game folder structure: delete the "Book 2 Saved Games" folder and everything inside of it. Restart the game and let it rebuild all those folders. Ensure the game is working okay. Then, go into your backed-up saved games and attempt to copy a save over to the newly rebuilt folder structure. Only copy the contents of one saved slot, not the entire previous saved game structure. Start the game and see if that one game loads. If any of these instructions sound complicated or confusing, don't do it!! You might really wreck something on your computer if you don't know what you are doing.