He woke up yesterday for me (messed up the date on day one). I had my balloon dog done first. He made it blue. I've also had him do my Astro Chair, Exotic Lamp, Piggy Bank (did it with a sapphire piece, looks beautiful), and a few other things.
Crystals can be used with furniture to make it shine, but it only works with furniture of the same color as the gem (Blue series with sapphire, green with emerald, etc). If you give him 3 gold pieces, he'll make you a piece of the gold series.
I'd guess he's asleep during wifi because the person who requested the furniture may leave before it's done and the spot would be taken up by their furniture.