Compatability of E6520 with PR02X docking station

I have the DVI/DP, VGA, serial ports working as expected, however none of the USB ports work (side 2.0 or rear 3.0)

Is there a specific Win7 64-bit driver for the USB hub inside?

USB Device VID=413c PID=2513

Listed as Dell E-Port Relplicator USB HUB according to USB IDs.

The only sites "offering" downloads are dodgy.

I've installed the latitude-e6520-windows-7-driver-cab, and the PR02X was sealed when I bought it...