Can't help with the thread messes, but wanted to say that I had to place a piece of masking tape on the front of my domestic machine to remind me to change the needle position for the scant 1/4". This has saved me yards and yards of ripping out 3/8" seams. Maybe you can do something similar to the front of your LAQ -- place a piece of masking tape there with the reminder to lower the presser foot, remove only after you lower the foot, and replace any time you lift the foot.