Swingarms are technically different, but the same casting is used....just a very small machining change. I was told by one of the engineers on the project that the difference in length is a few millimeters (small enough for the idler to take care of it). He said the driving factor to have it different was for marketing to try and differentiate it from the R. I have been told a R swingarm with work with the CR sprocket, CR belt, and CR idler bracket (the idler itself is the same from what I am told).
This is just what I was told by an engineer on the project. I have not double checked any of this information against the drawings for the parts.
Front pulley is the same as Cosworth has stated.