CTD issues

I ctd a lot on maps it seems like something has loaded onto the map when a rare dies or when a strongbox is opened that makes it so I can't re-enter the map. sometimes verifying the integrity of the game files solves the problem, sometimes it doesn't. very frustrating to get booted from the map before finishing it. happened 3 times tonight. so I'm done. I am not a coder but my guess is there is some file that gets loaded in or cant render correctly so it is causing a full crash to desktop.