Brillant forum thread, I have tried to add the policy at the end of the task sequence after the FEP Client task sequence which you explained above but it fails with the following which looks like it gets applied during PC Boot?
The program for advertisement "MK120056" failed ("MK100092" - "Staff Desktop Endpoint 2010 Policy"). The failure description was "FEP failed compiling the WMI class CCM_ISV_SoftwarePolicy. Therefore a policy cannot be applied to the FEP client, and the FEP client cannot be deployed. Error code: 0x1".
User context: NT AUTHORITY\SYSTEM
Possible cause: The program generated an installation status Management Information Format (MIF) file with a status value of Failed.
Solution: For more information about the failure, refer to the documentation for the program you are distributing.
Is there any other additional config needed?