If you run Reason 7 under Mac OS Yosemite (or El Capitan) and get an alert that says: "Repair required There is a problem with your Ignition Key installation..." here is a tip that might work:
Download and install the Reason 7.1.2 update, which brought Yosemite compatibility. While it's not officially tested and supported, Reason 7.1.2 should work under El Capitan as well (thee are users running this configuration successfully).