The Generic action allows you to run a Plastic SCM command as you would from the command line.
Provide a value for the workspace location (this field can be populated with the default workspace if you have specified one on the options page).
In the command field type a command as you would from the command line.
For example to run cm status you can either type cm status or simply status (either will be accepted). Provide any arguments to the command as you usually would.
Any errors in the command syntax will result in the action failing.