Karliah can be fixed when she stops to have the final chat, in the chamber with the 8 fires. Stand with your back to the barred ritual chamber and your face pointing to the stones where you get your armor. She will start walking in the good direction, towards the barred door and you MUST save the game at this point. When she reaches the barred door, she will use the chain one time too many and the bars will drop and then raise again. When that happens, simply bump into her so that she opens the door but doesn't close it again. If all is well, she will resume her walk across the ritual room. Note: This requires a bit of precise timing and remember to block her path to the chain until she is pathed towards her destination
das schon probiert?