Add missing CRW and related code:

Original CRW code was committed May 2011 (dc04e4858f0f1f5f60d8382a88c5085c7ebbdab3) but was accidentally backed out by Jan sometime later.  Mark's recent "Channel cleanup (Phase I)" commits (May 2013) re-introduced MOST of the May 2011 code, but itself accidentally missed some of it. This is the part that Mark missed re-adding such that the original May 2011 correction to our CRW handling is once again complete.