Try this on a plate or tray first so you can see how much to spray without dissolving the crystals and causing them to bleed. The syrup will evaporate off and the sugar will stay stuck. You should be able to find quicker easier ways, maybe brush some water icing on or even melted butter.
Stencils work well on dry surfaces such as marzipan and can be brushed with choc for quick effect.
Nice to use on top of molded mousse cakes too. I thought wilton went out of business.