Thanks everyone for all the feedback! Regarding previous gold doors turning silver, the probable cause is that we've added new levels in certain rooms that would turn the room doors silver. Also we've added new achievements to certain levels which could turn the door silver until you get it. For example, in one of the updates we added a star for collecting all coins in the first level "Alpha".
Thanks for the report. We are investigating the moving platforms. If you could send a screenshot that would be very helpful. The fix in the meantime could be to refresh the page.
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