That did the trick. Everything back in order except...
When the mage asks me to get a herb guarded by the evil tree, and I go out to seek it, it appears to have dissappeared. Oh well. No problem. Silly quest after all.
Oh and yes. In order to get the third part of the 'strange weapon quest' I should go to the Thieves Guild. Only, that door has been closed (by deleting the world.x1 file probably) ... is there an undo for that?