I have found that machines are finicky and prefer certain brands of metallic thread. I would try a few different ones on a scrap and see which one your machine likes. Hopefully it wont be noticeable if you change to a diff. Metallic on your project. Never heard of running thread Through styrofoam but you may also want to try using one of those gadgets that you put large cones of thread on. Not sure what they're called but they will reduce the drag of the thread. Also, try not threading through the last guide before the thread goes through the needle. Good luck!