Hi,
(After creating this post I added this clause. The post is a little long, sorry for my bad english)
Because monitoring by WMI is not supported and you are new to Zenoss I recommend you to use SNMP. In the SNMP option you can simply add windows process and see count, memory and cpu utilisation. You can use WMI and SNMP together.
If you have to use WMI only, there is a very difficult way.
The schema of this way is:
- add process name to the Zenoss (GUI)
- add this process do the selected device
- change its template to local
- in this template delete all data source, enter your own data source as command type, in its properties enter command to call linux script, add data points to data source, change data point in the graph
- in the meanwhile you have to create python script. The script have to use wmic command and ask for the counters of the monitored device for its memory, cpu utilisation and count of the process.
If this description dont scare you... 
The first step you have to understand 'wmic' command working.
Log in your linux server as zenoss user and enter 'wmic' command. This show you command usage. Try to use it.
After this you can think about python script.
Please let me know how you make it out.
Tommy