Return values of some WMI classes

I have a question regarding the output values of the WMI class Win32_PageFileSetting Class.

I am executing a WQL query, and want to retrieve the property values of InitialSize and MaximumSize. However, they return a value of 0. Since my pagefile is set to be managed by Windows automatically, could that be a reason it returns a 0 value?
Also, does that mean that custom page file sizes will produce other outputs? How would I know (using the WMI) that a pagefile size has been set to custom?

Thanks everyone!