OK so it sounds like it is probably not the motor. That clicking sound is the clutch, normal sound if the motor can't move the slide for some reason. I would make sure the TT was level then try it again. If no luck I would try to manually extend the slide with the hand crank.
Could be allot of things, out of alignment, a rock/pebble stuck somewhere or just need some lube on the rails.
Russ & Kim
2014 Alpine 3600RS
2007 Dodge Ram 3500 5.9 4X4
2008 Harley Davidson Road King 105th Anniversary
(2011-5 bad year)(2012-40)(2013-45)(2014-23)