Unit of count (revisited)

Ben, all,

This is not a critical point, still, I would like to hear your opinion.
Stemming from another context, I bring here a difficult question, 
related to the POE.UC.10 (link 
<https://www.w3.org/2016/poe/wiki/Use_Cases#POE.UC.10_Pay-by-Use>)
Please think of the policy I invented below. In a word, there are two 
permissions:
- "You can play an asset 5 times for free"
- "You can play an asset 7 times at the price of 5 AUD."

:perm1 a odrl:Permission ;
     odrl:assignee <...> ;
     odrl:assigner <...> ;
     odrl:target <...> ;
     odrl:action odrl:play ;
     odrl:constraint :constraint1.

:constraint1 a odr:Constraint ;
   odrl:operator odrl:lt
   odrl:rightOperand "5"
   odrl:leftOperand odrl:count ;

:perm2 a odrl:Permission ;
     odrl:assignee <...> ;
     odrl:assigner <...> ;
     odrl:target <...> ;
     odrl:action odrl:play ;
     odrl:duty :duty2 ;
     odrl:constraint :constraint2.|

:constraint2 a||odrl:Constraint ;
|  odrl:operator odrl:lt
   odrl:rightOperand "7"
   odrl:leftOperand odrl:count ;

||:duty2 a||odrl:Constraint ;
     odrl:constraint [
         a odrl:Constraint
         odrl:leftOperand odrl:payAmount ;
         odrl:operator odrl:eq ;
         odrl:rightOperand 5.00 ;
         odrl:unit <http://cvx.iptc.org/iso4217a:AUD>
     ] .
||

One may understand that there are 12 licit plays of the item (5 free and 
7 paying). Then... How to express that a certain play should be 
discounted from the "free" permission?
Someone else may understand that there are 7 licit plays (5 free, and 2 
paying).
Which is the correct interpretation?

Regards,
Víctor
(There was an email on 28/11/2016 12:30 by Ben on this constraint, but 
he did not ask on this...)