Need to Integrate with Evite for Response

[Rhapsody]

We use Prestashop with an organization that has social functions. In the past we used Evite invitations that allowed people to reply with a yes or no if they were attending. Since we have started using Prestashop we now get the postive replies and have people prepay for the events. The problem is when we try and do both Evite invitation and the Prestashop link for registering with prepayment, some people just reply to the Evite and need to be reminded to then go to our Prestashop site to register.

 

Does anyone know how I can have a positve RSVP passed back to Evite based on someone completing the purchase of an event in Prestashop?

 

Alternately - is there another solution that allows tracking of RSVPs and integration with Prestashop?