Dynamic Crm CustomActivity

Question

hi, 

  i am c# developer,currently working on dynamic crm 2016.i have to create custom activity in crm using Microsoft.Xrm.Sdk version 8.0.

        i have created custom activity in crm using  CreateEntityRequest but got an error regarding HasFeedback in 8.0 version ,

but when i created custom activity with CreateEntityRequest version 5.0 then it will created successfully.but our goal is to create custom activity using Microsoft.Xrm.Sdk version 8.0.

                 so please suggest me how to create custom activity in crm using  Microsoft.Xrm.Sdk version 8.0.