Grant permission to post a new node of content-type 2 if previous node of his content-type 1 has a state of approved I'm using Workflow module for an Article Submission Contest website.

I have two main Role defined in system:


Referee
Participant


The whole workflow goes like this:


Participant user logs in, submit his summary article (content-type).
System sends an e-mail to participant regarding receiving the
article.
Referee user logs in, checks the submission then Approve/Deny the
submission (Workflow module).
System sends another e-mail letting the participant know the results.
If Approved, Participant may send his Full Article.
Referee Checks new submission, Approve/Deny and Publish to the
website.
System sends a congratulations e-mail letting the Participant know!


Everything is setup already and working just fine, the part that got me hooked in Rules module is:


  When the Referee Approves the Summary Article (Content-type 1) via workflow module, then it
  gives the access to Participant to Create new node on Full Article (Content-type
  2)


I'd really appreciate any hints, comments, answers, beers and coffee's you may provide to solve my issue! thank you.
You can create two Roles.


Role 1 -> has permission to create summary (content type 1)
Role 2 -> has permission to create full article (content type 2)


you can assign Role 1 to users by default.

Next you create a rule like 


  Event : Summary gets approved
  Action : Add user role


The way you create the rule depends on whether you are using Workflow Node or Workflow field

If you are using Workflow Node then the rule  will be


  Event : Workflow state has changed 
  Condition : Check the state


If you are using Workflow Field then the rule will be


  Event : After updating existing node 
  Condition : Do a data comparison for the workflow field with the state ID.


Action will be Add user role, that is Role 2