Winches were not available in 2010 for the R21-EC. On my boat, I have to cock the anchor just right in the bowsprit in order to insert the locking pin. I then turn the pin to the locking detent, and so far, I have not had a problem with the pin coming loose or the anchor moving around. I have been in some pretty rough water and have not had a problem.
If your anchor is flopping around, I think knotflying had the simple solution - bungee cord. Beyond that, I think you would have to take a hard look at it to determine why it is flopping around. On the boats I have owned, the bowsprit has always tightly held the anchor.