Asus OnHub AC-1900 / AT&T U-Verse Pace 2 Wire 3801 issue....

Ok... Loving the OnHub but have the following issues and can seem to get resolve.

AT&T Modem/Router has the following attached:
1 - Computer (Windows XP) - Ethernet
1 - OnHub - Ethernet
1 - WD MyCloud Drive - Ethernet

WiFi is turned off and the OnHub is set up in the DMZ+

OnHub Router has the following connected:
Nexus 7
Nexus Player
HP ENVY 4500 e-All-in-One Printer
Chromecast

Here are my issues.:
1.) The computer can't connect to the HP printer for printing.... It doesn't see it at all...

Asus OnHub AC-1900 / AT&T U-Verse Pace 2 Wire 3801 issue....