Yes, Spirit Rock retreats, as longs as they are five days or more and silent, will qualify.
I have enjoyed training with the CFM very much. I would say our great strength is the quality of the programs we offer, together with our deep dedication to living mindfulness practice. Our challenge arises in meeting the high level of interest in our programs, which sometimes results in slowness on our part (as the lag between your message and this reply!) We are working on improving in this area.
I was already teaching meditation and yoga before I trained with the CFM, so for me it wasn't a matter of beginning to teach, but beginning to teach MBSR. It was a couple of years, if memory serves, from when I took the Practicum to when I first lead an 8 week course.
Hope this is helpful!