Ok, I was modding my game a few days ago, and my sister asked to play. I then went to my data folder, renamed it to modding, and renamed my sister's data folder to data, so It could run her mods. Now after being out of town for a few days, I try to get on my computer again and switch the data folders back to the modding one, and the construction set doesn't show npcs or creatures, it just says updated, and after a minute goes all grey. When I try to view a cell in the Render Window, the Set Crashes. I tried to see if something in the Construction Set ini had been changed to a bad value or something, so I deleted it and let a new one come back. Still not working. I tried to see if I switched out the data folder to another one, if it would work. It did. So now, any help?