I ended up with these nice looking sails and CAAS masts.
Here are a few pictures of the Naish sails 5.7 and 5.0 with CAAS masts 100C. Is this how these sails ought to be? I'm not used to rigging modern sails. Because I do not have Naish masts I'm not sure whether I am seeing good things or not.
A few comments. The 5.7 needs about 5 to 10cm more downhaul than indicated by the manuf. Could be due to the vario top which is difficult to get to the minimum setting. Once the downhaul is cranked down more, the leech gets looser and the battens near the boom are touching the mast. When I press on the belly of the sail, it stretches out and the shape looks good. Without any pressure the mast sleeve bulges a bit to the front. I assume this is how things are meant to be.
The 5.0 looks slightly better to me - the extension is exactly as per manuf, but I find that I need a slightly longer boom than indicated. The more I crank down on the downhaul, the longer the boom seems to want to be.
Thanks!