I'm currently rapid-prototyping with XD which works like a charm. I just got a problem with transparent pngs inside components in browser-preview.
Case 1: Component contains several nested components, all of them set to 100% opacity except not needed ones - everything fine
Case 2: Same component-combination. One nested component, containing several transparent pngs, set to opacity 87% - results in a greyish background of that component in browser-view. When changing component-opacity to 100% and image-opacity to 87% it seems to work again. Bit weird, but acceptable.
Case 3: Same component-combination BUT inserted multiple layers with transparent pngs, set to blending mode "overlay". PNG and component set to 100% (after former exploration ;)) but everytime I check browser-view, I'm getting a non-transparent result.