AppA ↔ AppB — what should happen

Trigger: When a “New Leads” index is checked in Mindbody

Client profile (email) goes to Constant Contact–Prospect Series which is an automated series of emails that they will receive. If clients do sign up, then we remove the MB index, and the automated series should stop.
I would like to also have other automated email series based on different indexes once this one is established. Please email me: pr@wcaom.com. This is urgent as we are currently using SyncApps for this process. Sync Apps is not going to upgrade to API 7.0, so our connection is going to go away any moment. Any help is much appreciated!