We basically run a system where we deal texas hold'em, and if you succeed at a relevant skill check, you get handed an extra card to use. It's not quite the same outcome for skill use as it would be, but it's a reasonable method to "skew the odds" in your favour.
I think the illusory duplicates made by the magic are designed to "move around in your space" to make it hard to tell which one is actually you - the purpose of the spell is to make you harder to hit, so it's behaviour probably works to let that happen. It'd also be very difficult to get away with it in a social setting because you have to cast the spell first, it makes four duplicates, and they don't last that long...
Now on the other hand... Trickery Cleric "invoke duplicity" allows you to control the movements of the duplicate (which is incorporeal), so it might be possible to hide it inside you if you were really practiced. Konsi sometimes summons it in her exact position while standing still, then uses her second channel divinity slot to turn invisible and run away.
It'll only give you cover for a moment, but if they're doing some sort of "check every visitor for vampirism" check on the door, it might get you past.
Aw man, imagine using technology to reduce the amount of time people had to spend working, rather than making rich people more money... what a crazy world.
Konsi actually has extremely good skin for a goblin, mostly because she's free of Maglubiyet's curse - but she has difficulty recognizing beauty in herself.
The piano is actually there because we needed a ballroom to entertain some NPCs for a political summit. Several of the servants in the mansion were skilled in instrument use, so we made a small area for performers.
The Dragon Skull is in the sand of a fighting/training pit for the party's fighter. She basically took out a red dragon single-handedly during one of our adventures, and it's a replica of that dragon's skull that we couldn't take away as a trophy because the dungeon collapsed.
I think, the first casting of MMM always needs a dedicated scene where the rest of the party get to explore what the wizard has made for them. It's a massive opportunity for creativity with the players, and as a DM you can just take a load off and let the wizard player run the session for a while, explaining all the cool things they incorporated.
The first time I cast MMM in 5e, it was with my pyrophobic gnome librarian wizard, Neff. She build a special room for each member of the party to cater to their needs, and I built a map for it (we were on VTT)
I don't think Ahdok is real.