Sorry you are having problems!
When you said "Feet Down" i'm guessing that's feed dogs down. Also you said it happens when you move to another area. So you are actually lifting the needle & presser foot to shift the fabric. Are you sure that you are lowering the presser foot when you get to the new area? The loops on the bottom are the classic symptom of no tension on the top thread, and the way the tension is applied is when you lower the presser foot.
Maybe someone else will have other suggestions.