Maybe I just have bad reflexes or something but I found the picking mechanic very unforgiving. It would often take me anywhere from five to twenty tries each lock. The penultimate time I played it I left the attic 'til last, not knowing the mechanic change that would happen. It made it so that (nine times out of ten) there wasn't enough time to actually pick the lock. On my final playthrough I was able to complete it. That felt incredible, maybe because I had a lot of difficulty with it.
The idea is novel and the assets are all wonderful. The sound effects really do a lot in the way of making it more engaging. The only improvement I could think of is to make the picking either more skill based or more forgiving. Great use of the theme