At what point in the story are you in regards to the alchemist?
Do you have any recent (or not so recent) saves you can try, at least to see if the problem exists in them as well?
The dynamic folders are;
'..\Beyond Divinity\Acts\Act1\Dynamic', '..\Beyond Divinity\Acts\Act2\Dynamic', etc.
These folders are used as a cache for the game. Files are created / copied there from the save game folder when you load, and written / copied to those folders when you save a game. If there is a corrupt file in those folders, deleting the files should fix the problem. The files will be re-created as required the next time you start Beyond Divinity.