I set mine by the Goose Marine site they have a great tuning guide that explains why you do the settings on the boat. Highly recommended
Go to Goosemarine.com.au click on articles then search out Tuning guide Nacra 5.8
The recommended tension is that you cant make the diamond wires touch the mast 18 inches up from the adjuster. When you read the article it explains why and what adjustments.
Catsailor.net has a great photographic tuning guide go to forums, then Nacra, then Nacra 5.8 Tuning guide it explains what several top boats did in a race series with their diamond wires. If you find you can't point too well on one tack check your tension when mine was too loose it made me go off the course because the middle of the mast bent into the slot depowering it.
As for the hole, sorry really need to know how and where you put the hole in it and how big to work out how to repair it.

regards