Common aggravations with CS include sticky runners, stiff in chocks. They may have been fine after building but now have absorbed a bit of moisture and don’t rotate well creating significant drag. Do something. A “Red Devil” paint scraper good and sharp works well to shave the inside of the chocks. Check that surfaces are flat and keep scraping until runners rotate freely without sideways play. Do most of scraping on outboard chock. Wax chock and runner body heavily. Of course if runner does not have “Formica” sides you can just sand/scrape that wood. While you are at it saw off extra threads on the runner bolts and make it easier to set up.
Often builders leave corners of wood on the fuselage square and sharp. This is going to hurt sooner or later when you fall on it or it falls on you. Round them off, the boat is angular enough without all the corners. One builder noticed that his boat seemed heavier than the prototype, his “2X4” sides are really 2X4 rather than 3 1/2 X 1 3/4 lumber yard size. He could rout away some of the extra wood or even just unscrew whatever screws held it together while the glue dried and saw 1/2 an inch or so off the sides. Another builder wants to amputate some of the rear lunch/tool compartment so it will fit in his van, why not? Where is the sheet going to attach, the back of his helmet? The technical and protest committees do not exist.
The skinny bed rail runners cut through crust and snow noticeably better than 1/4 in. DN plates they work well in slush too. I have a pile of free bed rails for anybody. Long runners seem to slow the boat down tacking and jibing more than the short plans built bed rails, probably due to light weight and inertia of the boat as well as dragging less runner around the turns. The speed advantage of longer runners may not be apparent since we have not taken up serious racing and the CS isn’t very fast anyway. There are design trade-offs.