However you resolve this, I suggest you replace whatever is securing your "down rope" with this:
Learn about the Auto Release cleat from Clamcleat®. For rudder downhauls or load sensitive applications. Prevent blade damage. Easy to adjust and reset.
www.clamcleat.com
It pops loose and releases the rope if too much stress is applied, and is adjustable.
I have a Hunter 170 and installed one for the rudder and the centerboard. I got tired of the damage that was caused when I struck bottom.