The only thing I could possibly add is to try using Sewer's Aid on your needle thread. I had a problem with thread breaking when I first started fmqing. I tried EVERYTHING. I really believe it was the Sewer's Aid that finally solved my problem. I used to be able to buy it at Hancock, but the last time I had to order online. It comes in a bottle that looks like fray check. If you are placing an online order, I also highly recommend bobbin genies. I think sometimes it comes down to the right combination of "tricks" for each person and machine.
Good Luck and keep us posted.