I don't see a problem with the door.
I assume either your game files or the save has a problem. To ensure that you have no broken files, you could try to re-download the full game, and copy&paste the entire content of the www/save folder from the old game to the new game folder.
Else, send me the save file with the save slot number that has the issue to Naughty-Netherpunch@web.de and I'll check if the save is fine.