you do have to adjust the tension and maybe even use a net over the spool of thread. try changing position of spool from vertical to horizontial

the monofulament poly is not stiff

you may still need the "sock" that comes with the thread to keep it from pooling around the spool as it comes off of it. I have yet to try FMQ with invisible thread. good luck.

I took a thread course a number of years ago at my LQS, and monofiliament thread was discussed. The instructor advised us that polyester is a better choice over nylon. If you check the Superior Threads web site and look up the information on monifiloment, you will find poly thread is preferred for reasons such as being pliable, dryer safe, will not get brittle and so on.

I have been advised and requested to never use this type of thread on a quilt for a child younger than 6. It is because if the thread becomes loose the child can become entangled, the thread won't break and there could be serious injury.

I use YLI invisible threads and put it on a single thread stand behind my machine. I run the thread through the loop at the top of the stand over to my embroidery thread stand and then to my machine. Going through 2 thread stands seems to keep the twisting under control. I use it for stitch in the ditch., free motion stippling and designs, and binding.
Good luck.

I've also heard that you have to slow your machine down when using this thread. Going fast heats it up, also check on the type and size of needle. I started using inpira needles because the top of the eye is flat so the thread has a flat service to glide on and not a pointed one as most needles have for the eye.