Dude beta 8 and Juniper Screen OS firewall SNMP

I am trying to monitor the CPU and interface stats for my Juniper ISG 2000 firewalls. I have retreived the MIBs from Juniper for the NetScreen Resources (cpu, mem, disk, and interface) and am trying to poll the current CPU and interface stats, as well as have them appear in the historical graph tab.

How do i configure a custom snmp polling agent to show % utilization?