We will have to read rule 40 As indictaed in section 6 of the NOR. The table in section 6 could be contradictory as it reffers to another source of information. I will check Castle Cove's website.
Tow ropes aren't very relevant to cherubs as they tend to fall over but better to try than sit drifting around in Weymouth Bay. The NOR doesn't state how long a tow rope should be. 1m?, 10m? or 20m?
At the end of the day if a boat is found not to have the correct safety equipment it could be disqualified.