Ok I was able to finally resolve this in Linux Mint 17.2
Not sure exactly what change fixed this but I did as follows (after swoogan's automatic installer failed)
Created a file /etc/modprobe.d/usbhid.conf
in which the only line I put in was: options usbhid quirks=0x0c45:0x7603:0x0007
Created a file in /etc/default/grub.d/ named aziokbd.conf
Contained the line: options usbhid quirks=0x0c45:0x7603:0x0007
Copied this file to the etc/default directory
Copied it to etc/grub.d directory as well
(Not sure of the last two items helped or not, but I did it just in case)
Finally added :
Directly to the Grub conf file located at: etc/default/grub.cfg
*I believe it mentioned this in his instructions, but I was thrown off by the missing .cfg after grub. I assumed it was a folder etc/default/grub
Ran sudo update-grub and restarted. Now my perixx 1800 keyboard works.
Hope this helps someone.