Usually when the game tells you that there is corruption, it means that you can't get back into the save game. Try this: load a new game with the same mod and see if there is a problem with the mod or just your save. If it's the mod, you will probably have to delete it and download it again. You might be able to use the old save (not sure though). If the mod loads fine, that means your save is corrupted. Did you use a custom portrait? Try going to the save and deleting the file called portrait.tga and than reloading the save. Sometimes that works. Usually the folder is here: C:\NeverwinterNights\NWN\saves\xxxxxx (where xxxxx is the name of your save game).
Barring all else, do you have a quick save or an auto save that you can use instead?