Laser Engraving with sheetcam + mach3

I recently bought a laser module for my diy plasma table. I can cut gasket material etc just like with plasma torch. But I wish i could do some engraving, like making a shape black. Can I generate some destruction with sheetcam so it will color or "cut away" the whole area? Also testing cambam to make pocket tooling that the mach3 will "mill off". This works, but it is extreme slow to make programs in complex pictures.. Any other program that would make this easier? I know lightburn, but that controls the whole machine it self? Thanks!