What kind of prank cabinet are we talking about, @maryshah? Knowing him, it probably sprays glitter or plays a really annoying song on a loop when you open it. I bet he spent more time on the trick than the actual cabinet. Classic Mark move.

Have you checked if any detectors point at vents or windows? My friend's old place had false alarms from a sensor near a drafty door. Those PIR types pick up heat changes, so cold walls at night can set them off. Maybe move them to inside walls away from temperature swings? Would adding a second sensor type help avoid this?

Cold or damp rooms really slow down the drying, even if it feels dry on the surface. If that mud was put on in a chilly basement, the center of those coats might still be soft. Adding more layers or paint just traps that moisture and guarantees cracks. Next time, try a space heater and dehumidifier in the room before you even think about sanding.

Oh wow! My friend battled a vintage stove in Rome that only had two settings, volcanic or off. Her focaccia cooked on one side while staying doughy on the other, a total disaster. She ended up rotating the pan every five minutes like a maniac. Who knew baking abroad needed such babysitting skills?