Will sugar water prevent raw wood from cracking as it dries?

No, not at all. It will accelerate the drying and rotting process. The best way I know to preserve and strengthen raw wood and prevent cracks in one step is bathing it in teak oil. The downside is teak oil takes two or three weeks to dry and harden enough to put any other stain or finish over it. But it does protect and strengthen the wood fibers deeper inside the wood than anything else, and it can stand alone as its own finish. It gives the wood a permanently wet color. It creates a pretty natural raw look, but it isn't a totally professional looking finish unless you varnish over the top. If you use the boiled linseed oil you can get a nice gloss finish like a gun stock.