I've encountered the crashing to desktop when Bartering as well. It happens specifically when I come from camp to a trade like Tahli at the Last Light Inn. Select Barter change the items so their entire inventory loads. Now drag some gold into the barter window - crash. If I put an item from the trader into the barter window first then it appears to work fine.
I have no mods, never had issues prior to patch 6 with crashing etc.
