Missing graphs with WMI monitoring

Good afternoon everyone!

I have recently taken on a partially configured installation of Zenoss. I am relatively new to Zenoss and although have managed to get my head around some of the basics, although I am struggling to get a few things into place.

The Zenoss installation itself is Core 4.2.4. The devices of interest are being monitored in a device class setup to monitor via WMI. The ZenPacks.zenoss.WindowsMonitor Zenpack is installed, and the zenoss.wmi modeller plugins are enabled for the device class. I have also used a service account that has full local admin rights on the VMs I am trying to monitor.

I have added a number of VMs to the device class, and for all I am seeing the same behaviour. Under the components section, I am seeing what I believe to be correct information for Network Routes, File Systems, Windows Services and Interfaces. For Processors, I am seeing information on the processor but not any statistics or graphs on usage: http://estrale.com/pics/1.png

Under the graphs section, I am not seeing any data and am getting the error message phythonThresholdException: User-supplied Python expression (here.totalBlocks * here.blockSize / 1024 / in a yellow bar at the top of the page (note the graphs have never worked, but I have not always seen this message so I dont know if the two are connected): http://estrale.com/pics/2.png

Under monitoring templates, I have the following for Device_WMI: http://estrale.com/pics/3.png

The only error of any significance in the logs:
Resource: isddswds01.ad.ucl.ac.uk
Component: zen.winperf.PerfRpc
Event Class: /Status/Wmi
Status: New
Message: Bad Counter(s) - 10 bad counter(s) for device 10.10.111.26
details: \Disk Read Bytes/sec, \% Disk Read Time, \Disk Write Bytes/sec, \% Disk Write Time, \Free Megabytes, \LogicalDisk(\\\Volume{cedd2855-d7ec-11e2-93e8-806e6f6e6963})\Disk Read Bytes/sec, \LogicalDisk(\\\Volume{cedd2855-d7ec-11e2-93e8-806e6f6e6963})\% Disk Read Time, \LogicalDisk(\\\Volume{cedd2855-d7ec-11e2-93e8-806e6f6e6963})\Disk Write Bytes/sec, \LogicalDisk(\\\Volume{cedd2855-d7ec-11e2-93e8-806e6f6e6963})\% Disk Write Time, \LogicalDisk(\\\Volume{cedd2855-d7ec-11e2-93e8-806e6f6e6963})\Free Megabytes