Are you referring to the clear nylon thread? I've used it. I had to play with the tension a little bit.

If you want to sew with the clear nylon thread, this link may be helpful.

Here is a link that might be useful: Sewing with invisible thread

I held my breath the whole time but the nylon thread did work. Thanks.

Normally you only use the clear nylon thread for the TOP thread. Use "regular" thread for the bobbin.

I have used nylon thread or polyester monofilament thread with no problem. I have used it in my bobbin as well as my needle for machine quilting. Make sure you purchase a good brand like Sulky or Gutterman as it does make a difference.