First of all, I'm not an expert in WMI - so maybe I'm wrong. But what I understand it, it's not possible to call WMI methods using WQL - and WMI.Query is based on executing WQL queries. It is possible to create another parameter for WMI subagent, WMI.Call, which will return result of calling given WMI method. I add this to my to-do list, but because WMI is almost unknown area for me, it may take some time until I implement this.

Best regards,
Victor