How to trigger activities in sub-flow Simultaneously

Hi all , 

 Here am having one problem with sub-flow manipulation , I have two flow in my application main and sub.

 1) mainflow and 2) subflow.

In the main flow have two activities those mapped to two forms and one sub-flow element this subflow element mapped to subflow. 

In subflow have one activity that mapped to a form. 

What am trying to achieve is when the Main - flow/process trigger the sub flow(sub process ) , the activities in the sub-flow need to start simultaneously and the forms should need to be popup automatically. but when try to achieve this the activities in the subflow is going to the Inbox . What am doing wrong in this , can some please help me to trigger this out. 

Here am attaching a test app that have I created . 

APP_test_workflow-1-20120830214025.zip