I am at the point of "defeat Alduin" After doing shouts of clear skies the fight begins. I hit Alduin with Dragonrend. He does not land. I do this over and over again. Yes I see a blue cloud wrap around him. I also notice the my arrows do no damage. If I keep moving and stay alive I see the others do damage to him. Very Slowly. But I can not make him land or damage him. I have even made it to the point where he only has a sliver of life left. None of that damage do to me. That took me over 2 hours. He never lands. And I can not hurt him. It appears that I must be the one to do death shot because nothing changes. Alduin just flies around.
If I don't get past this I am guessing that is the end of the game for me. The last save that is not affected with this is over a month ago. To me that is a lot of quests to have to redo again.