Wierd quest and my game bugs out.

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First of all, im using Civil War Overhaul and this bug is probably related to it.

After completing the Civil War (by taking over solitude) i went to Potema's Catacombs to, you know, kill her when this quest pops out. A while later i cannot sneak, attack or do anything other than walk around and jump, i cannot even activate doors.
I tried loading a save before the quest started and went somewhere else, and it worked for a while (enough time to go from Solitude to Darkfall Cave, the one with Auriel's Bow) and then the quest showed up again. Just as before, a few seconds after the quest started i was no longer able to do anything other than running around, much like in the opening scene when your hands are bound.