I actually have never uploaded stuff before, so I, myself, am not 100% sure how it all works ;O Shocking, I know lol! shhhh.

But - Sasha has made a few things and she'll know for sure. [She's asleep right now, but I'll ask her tomorrow and then let you know :) ]

I've d/led furnished houses many times though, and I assume if you put them in, they'll stay in - as long as you upload them, of course lol! There's a step by step guide here for MTS2. Also read the Creator Guidlines if you haven't already.

Hope This Helps :)