I currently don't see where the bug is. Is something not spawned or the ground tile being messed up?
Please go to Settings -> Mod settings and enable debug mode for my mod. Then try to reproduce the bug again. Now Factorio has written important og messages I need to see what "my" mod did over there. Please paste it here in the thread and not in some pastebin. You can do so very easily by starting the paste with 3 backticks, paste the logfile's content and finish it with 3 backticks like this:
xxx.xxx Script @__AbandonedRuins20__/foo.lua:xxx: Some debug message, variable='value'
