RE: North sails mast compatibility
It dpends on how you apply the specificiations?
I checked the North Sails 2007 specs, and the 6.6 m2 Natrual does not have an adjustable head strap
The mast needs to be a 460 cm IMCS 24-26 extended out to 474 cm (that's 14 cm of additional mast base extension.
Then you need to check your mast base against a North extension to see if your pulley sheaves are the same distance from the mast collar on the base.
All of these things could add up to you needing to put to collar 1 or 2 holes higher on the mast base to get the correct tension and get enough downhaul to pull the batten above the boom back to at least the middle of the mast.
4-8 cm seems tike way too much outhaul, but you need to check the VTS (Visual Trim System ) to see if you are getting enough downahul.
If the scallop in the uppeer panel of the sail is not extending in from the leech to the VTS dots, then you definitely need more downhaul and the only way to do that is to extend your mast until it's long wnough so you can bend the mast, completely with downhaul until the leech loosens to the Trim Dots.
Then use the outhaul recomendations that are printed on the sail out by the clew.
So, in summary, you coulld have a compatability issue, especially since the sail is designed on the North "2 mast" system.
Hope this helps.