This seems to be tied to a bug some other people have experienced where new levels don't load correctly and are overwritten with existing levels.
Try going to level 15 and resetting the level (Ctrl-4). Does that help at all?
Try going to level 15 and resetting the level (Ctrl-4). Does that help at all?
(Update: Each time I enter a level, it loads as level 13, and I have to reset it to get the correct map and code -- just a heads-up in case it helps with debugging. Chrome 33.something, Windows 7 x64.)