MOQ and readonly properties

[Gordon Johnston]

I am trying to MOQ a CRM Plugin.

The plugin receives a number of properties and I want to ensure that the code flows into the correct IF statements depending on what type and state the record is that triggered the workflow. 

I am new to MOQ so it may be that I shouldn't be doing this or that I need another method to generate the incoming data and parameters.

I suppose my question is: Is it possible to force in a value of a readonly property?  I am trying the SetupProperty method.

As mentioned I have no control over the property.