I have the 8200 and I love the floating foot even though I've only used it a couple of times, my FMQ made me so happy using it so sorry you're having trouble.
Do you iron your seams open? I do all mine open and haven't had any problems with snagging. I use the open toe foot and adjust the screw so the foot is touching but not dragging on the fabric.
I'm still a complete novice at FMQ really, but here is an example of my work. These are the first and second attempts at FMQ on my 8200. Prior to this I had done a few pieces on my old machine but never been happy with them
First attempt on 8200:
2nd attempt:
Edit: I leave the thread tension on auto, and use the stitch mode that it says in the manual to use for the free motion foot, can't remember what it is off the top of my head!