Hi, thanks for reporting those bugs. Do you have build #190 or #191. #191 has lots of fixes for generation, although it is possible that I did not catch everything. Could you send me a log file, please? To contact@voidroom.com. One log file that was done when you run into one of those issues could be enough. Logs are located in subfolder "_logs" in folder where you put the game.
I got crash reports when level can't be generated at all but not when there is just a wall in front. Although I run into a few different bugs that were resulting in a corridor incorrectly generated, it was collapsing onto itself. This could result in a wall on the way (although in cases I had it was so weird, that it was right behind the door. Noticed that only because I was investigating something else.