Something is hung up
Not familiar with Facnor roller furling, but they are all similar. If the furling hangs up after a couple of revolutions, you have a problem with something causing it to foul (most likely culprit is the jib halyard, or spinnaker halyard). On my S2 7.3, I installed a Schaefer SnapFurl system, which has a two piece plastic sail furling tube which snaps over the head stay. Had two problems with it. There is an extra guide on an arm which they sell (should be standard) which guides the line onto the furling drum. Need to have that or need to be sure that the guides on the deck are located such that the furling line is always guided into the center of the drum and does not get hung up. More serious problem is the jib halyard. Coming off the upper swivel, the jib halyard must be held away from the upper end of the roller furling tube. Most times, the angle between the halyard going over the sheave at the mast head and the roller furling tube is sufficient to keep them away from each other. In my case it was not, sometimes it worked, sometime it did not. I had the jib halyard wrap around the furling tube (without realizing it). When the furling line got too tight to furl by hand, I wrapped it around a winch and continued to crank it in. After about five complete revolutions of the furling tube (it is amazing how strong plastic is sometimes), I realized something was seriously wrong. I should have stopped and unfurled the jib, but I released the jib halyard tension instead. The sudden release of force caused the forestay to snap (thank goodness I was at the dock at the time). I ended up having to replace the forestay (it broke at a swage fitting and was probably due to fail anyway) and the plastic furling tube, which had taken a permanent deformed twist of three revolutions. I also installed a deflector fitting onto the mast near the top, to keep the jib halyard coming off the upper swivel fitting at 45 degrees. When I installed a spinnaker halyard, I made sure that it would not foul the roller furling tube at any time. I also do not use the winch to furl anymore, if you can't furl by hand, something is wrong.
