Okay, I know this is cheap, but its useful if you're a weak-ass sorcerer with 60 hit points.
Okay, this is how it goes. You need to have shapeshift self memorised. Add the debug line to the baldur.ini file. Start the game, and cast shapeshift self, and shapeshift into a flind or whatever. Now with the cursor on your characters portrait, press ctrl+r(estore). Now look in your special abilities menu. You have permanent shapeshift, even after you sleep, and you can use it as many times as you like.
Enjoy
Permenent Shapeshift Bug 
Linear Mode
