I didn't find whatever you added for "digital code" to key puzzle... One key opens drawer for book, 2nd key goes behind picture and "clicks", but nothing happens, and I haven't been able to figure out anything else. I think you need to give us a bit of a hint on this key thing
Also, is there supposed to be any interaction with the woman all the way down the street we can't get close to? Is she supposed to be the 4th spanking?