I have had this problem on multiple characters. The issue appears to be that since the update some of my characters default guns are missing. The missing gun is still selected even tho it's grayed so when I try to change a character card the game contacts the server sees I have a gun equipped that I don't own and crashes. Forcing me to quit the application.
Once I select a different gun, I can edit the character fine but the default gun is gone.
However when I select Shae who is using the default gun I can't even see her loadout screen to select a different gun. It just brings me to an empty page.