I had the same exact problem! I go in the game, click tools, then map maker. when I go to world, I type ing the name of the terrain, i even made sure PNG was capitalized, and the terrain i made was a test, so it was solid white, the exact right size, and when I press enter the game closes and i says in a window called FeralHeart.exe, "FeralHeart.exe has encountered a problem and needs to close. We are sorry for the inconvenience. If you were in the middle of something, the information you were working on might be lost. Please tell Microsoft about this problem.
We have created an error report that you can send to us. We will treat this report as confidential and anonymous. To see what date this report contains, click here." then it has buttons that say Debug, Send error Report, or Don't send. the first time i clicked debug and it didn't work, and so far I haven't found anything out other than Debug does not fix the problem. is that the same window that appears? and has anyone else had this same problem but fixed it? thanks.
