Nagios Watchguard monitor

I recently installed this on my XI host (free license) and while it is able to ping my Watchguard XTM23, it it unable to poll active connections, received packets, sent packets, total received bytes and total sent bytes, which kind of makes it useless. The error is the same for all of these items that do not work: UNKNOWN – Invalid OID, no value found at this place! Any help getting this to work, would be appreciated. Thanks!