I was playing the game and then, randomly, upon booting the game once I got a fatal error! I reinstalled the game and it still came up! I'm assuming it has something to do with save data, but I can't actually find the save data. Oh yeah, awesome game by the way, but this error has prevented me from playing it for a week. The error itself is something along the lines of "fatal error in room creation code for room 0, expected some number (yygi32) etc.".
Oh shit! Well hopefully you were enjoying the game up until that happened lol. That is really weird, I don't think I've encountered that error before. If you take a screenshot of the error screen I can try to help you fix it, but like you said, it probably has something to do with the save data. If you go to your Appdata folder (C:/Users/[your name]/Appdata/Local), there should be a folder called Gun_Rounds, and if you delete savegame.sav from the folder and try restart the game, that might fix it. Fingers crossed!