"the keel is fixed internal" why would you have keel bolts then? Its actually externaly mounted led ballast with keelbolts. Take a look if any of te keelbolts were sistered? Evidence from inside the cabin that keel bolt was cut off hole patched and new bolt inserted next to it.
Anyway, the C&C smile is normal. But i would investigate if the crack goes all the way to the bilge. I.e. is there water weeping out? Get a surveyer to put a moisture meter to see if there's elevated moisture readings around the crack or bad core(delaminated or wet). When i bough my 38 the crack was all the way around. But it was normal. I did some work to eliminate the crack. Namely dig all the old fairing out, and wrapped the area in 6" fiberglass tape 24oz cross weaved (http://www.mertons.com/Reinforcement...le_stitch.html
). The crack has not come back in the leading or trailing edge in two years of sailing. It came back on starboard side midway for about 2 feet, but that was due to negligence of letting the blge freeze one winter. I just dug out and repaired that crack and will make it a point to not let the bilge freeze.
The flexing from backstay is normal. Thats why you have the backstay adjuster so that you can release it after you drop sails. Don't warry about the door not closing when backstay is tentioned. Hydraulic adjuster is a nice feature to have to spill the main when you get overpowered going to wind. You can put a lot of rake on that mast. And it should have a lot of rake otherwise theres too much pumping which can lead to fatigue on the rigging terminals. My upper shrowds are at the rigger at the moment because pumping caused some fatigue on the upper mast tangs.
Another important thing is to get a wooden mallet and do some tapping on the balsa cored hull. You'll get good at recognising the hollow or delaminated areas. For instance I have dry but delaminated areas where the port side stand was pressing on the hull. the surveyer said its nothing that would stop me from ocean voyaging so I am not gonna swet over it, but its good to know that its there.
Whats the new oversize rigging? Dayform, -12 rod?