The Rane FOUR is now supported in Virtual DJ Early Access build 7524.
To enable Early Access in VDJ, open the settings menu, click on Options, then search for early access as shown below. Be sure to click Yes.
You can also download the Early Access 7524 build using the following link:
Virtual DJ Early Access Builds
Please note, a Pro license for VDJ is required in order to use the Rane FOUR.
For more information on obtaining a Pro license, please visit virtualdj.com