I have this issue on my work PC but not my home one and it's defintely got to be something to do with moving the My Docs folder I think. In fact as well as the immediate crash after starting I cannot save my profile at all as Raze mentions above so every time I restart I have to create the profuiel again!
My machine is Windows 7 64 bit.
However, weird thing is, if I change my video settings, the graphicsProfiles file in the Documents\Larian Studios folder immediately updates so the program is well aware of where I moved my 'My Documents' to! (I have mentioned this before on another thread so sorry to repeat myself). Also the playerProfile file updates to whatever profile name I create when starting the game. But it never creates the associated folder for that profile name.
Today I copied the complete Larian Studios folder to the Documents folder from my Dropbox backup. I then kept the Larian Studios folder open on my second screen while the game started up. It did not see the files I had copied there even though I made sure I have full control permission and that I was the owner of the newly copied over Larian Studios folder. I also set the EoCApp.exe file to start as Administrator.
I then created a new profile after restarting the game and called the profile the exact same name as the folder I had copied from Dropbox, as I clicked OK to this the profile folder I had copied from Dropbox disappeared from the Larian Studios folder but a new one was not created!
Sorry if that was a bit complicated, not that easy to explain
So, no good news but just though that might save others a little time finding out