As for your other questions, other types of wood (not diamondwood) , you dye/stain them before laminating in the limbs. They will retain their color under the clear glass. After shaping the limb, you lose the stain from the edges of the limb, not under the glass. So you touch up with stain on the edge with a q-tip or brush.
Diamondwood, each layer is stained before it's glued, so each layer is different color. You buy the color you want, no staining required after shaping the bow. Many color combos available.
Dan