I'd like to use the alternate USB communication to hook my MK2xx (LK202-24-USB) to the internal USB header of my sapphire motherboard.

The mobo reference manual says:
1 vcc
2 gnd
3 usbp1-
4 usbp0+
5 usbp1+
6 usbp0-
7 gnd
8 vcc

The MK2xx reference manual says:
1 +5v
2 D-
3 D+
4 Not Used
5 Ground ...