I'm like siman, the software element is purely track transport, ie simulating the traditional decks, and track storage / selection- the mixer is handled by good old analogue mixer, pitch, jog, nudge by controller, its essentially a fancy cdj set up with a fookin massive easily browsable track selection on hand.
As for the worry about touchscreen, its tried and tested, its how the Emulator works, its a large see thru touch screen with the controls back projected on to it, as you can see it works fine