Grissom Academy/Geth Consensus Glitches

I have played this game through several times. Only recently (after months of not playing and an update) the game is full of glitches.  Most especailly Grissom Academy and the Geth Consensus:

Grissom Academy: Not only are there visual oddities (eyes rolling white and mouths not moving with words) but there are two game stopping glitches:  1. When you first reunite with Jack against the Atlas, once the cutscene is finished, Shepard falls through the floor into space and dies; 2. If you manage to get past that floor glitch, after you fight through the throng of Cerberus soldiers at the shuttle entrance, either the door won't open or you, yet again, fall through the floor.  I can't figure out a work around.

Geth Consensus:  When you get to the second level, the Reaper virus won't dispell when you fire upon it (the ones attached to the nodes).  You can empty the gun's ammo at it, yet it won't disappear.

While neither of these are game stopping, it is annoying, especially for those of us wanting to rescue kids from the evil that is Cerberus and dismantling the Reaper hold on the Geth.

If anyone has figured out work arounds, please post here.  I know there are many other players who have experienced these (and other) glitches.  I can't even mod the issues out.