Symptoms

The WFC Test Client has the ability to drill down into the different segments in a Lookup box however K2 does not have this same feature.
 

Diagnoses

- Set up an end point WFC Service instance in BP which uses complex queries as part of its SmO methods.
- One of the methods has a required parameter.
- Setup a WFC Test Client which replicate the K2's SmO for the WFC Service instance.
- The WFC Test Client has the ability to drill down into the different segments in a Lookup box however K2 does not have this same feature.
 

Resolution

You need to serialize the first object (which will return JSON ) then pass it to the second serialized property and then visa versa for the Load and Get List.
For information please look at:
http://help.k2.com/onlinehelp/K2blackpearl/DevRef/current/default.htm_K2_OData_Service_Broker/Complex_Types.htm_tracksearch=complex types
http://help.k2.com/onlinehelp/K2blackpearl/UserGuide/current/webframe.html_Complex_Object_Web_Service_Example.html_tracksearch=complex types