Hi there.. the method that calls the process depends on the specific application. In the Emergency Service application I've create a Helper class (specific for this domain) that is in charge of interacting with the Drools session that host the business process.
If you take a look at the class called EmergencyService: https://github.com/Salaboy/emergency-service-drools-app/blob/master/emergency-service-app/src/main/java/com/wordpress/salaboy/EmergencyService.java you will find that is the one that signalEvents, insert new emergencies, etc. For this application I've modeled the startProcess Inside a business rule that for each emergency that it's inserted in the KnowledgeSession a new business process is started. This way of modeling the situation gives me the flexibility to start multiple things when an emergency happen (for example I can start multiple processes to do parallel things when an emergency happen).
I didn't understand the note about the repository is down, do you mean that github is down? I was working on the app and in other projects today and seems to work correctly. Can you share the URL of the repository that it's not working?
Greetings.