MPC REN, DAW, Scratching...

If I want to record DJ scratching into my DAW, over a beat I exported from my MPC REN, I'll need an addition interface correct? I don't want to "sample" my scratches into the REN. Thanks

No, you don't need an additional interface, you can set up your DAW to use the Ren audio interface for both recording and playback. All you need to do is hook your decks up to the Ren inputs - then set up an audio track in your DAW and hit record in your DAW and record your scratching to that audio track - the audio will just pass through the Ren inputs directly to the DAW. The MPC Software doesn't even need to be launched in your computer.