It happened on v19 and it's happening on v20. After reaching Tier 5 on a Trator/Trader Joe mission and completing the mission, I go back to the trader, and request another mission. which is usually at the same location (building as the previous mission. When I press on the exclamation point to start the mission, the gut (interior) of the building glitches and disappears, to sometimes include the ground. I can't complete the mission. I've tried placing items such as frames or plates, and sometimes it will generate what should be in that location. On other locations, when I try to place something on the ground, the system "eats" the frame (it reduces my inventory but items is not observed placed on the screen). Even if I exit and start the game, the mission cancels, and the building is still glitched out. It happens with big buildings and on Tier 5 missions after they are completed one time, and they are going to by completed a 2nd or 3rd time. I have all screenshots in Doc format and available upon request.