I got the helm of Winterhold, but the dragon priest corpse is on the gate which won't open? The button won't activate? Is there any reason to try to go back and replay the dungeon in hopes of not getting glitched out of the back room? Or should I just go since the dungeon is cleared and the main objective (Helm) achieved?

Do you want both helms from there?

First game Yngol worked fine for me, and got both helms at two different times. Second game, did the Helm of Winterhold first, and the dungeon never worked properly again.

It happened to me too, yesterday actually. I read shortly after that if you re-enter the dungeon, it should work/open. I didn't try it myself though.

Thanx, didn't know there was a second helm. Hate to miss anything cool!