So i've pinpointed the trigger that's causing the game to crash to desktop while on the Nexus

After i've spoken with the Angaran Diplomat for the first time on the Nexus (there's a short cutscene in the Cultural Center) i am no longer able to walk across the Commons area without crashing the game. 

The only workaround i've found so far is to simply avoid that cutscene altogether and not meet with the Angaran Diplomat at all. It's not a real solution but at least it allows me to be able to enter the Tempest and get to other parts of the game.