Hi Seme,
We have been building Smart Tasks, and now it is a bit dev stuck (basically because of time). Currently it is used in Emergency Services project:
https://github.com/Salaboy/emergency-service-drools-app
We have some more things we would like to implement, but what we have now, it works for Emergency services requirements and it can really help you to build your application. We will be glad to help you integrating it with your application, as it would also help us making it grow.
You can take a look at Emergency services web application that uses it:
https://github.com/Salaboy/emergency-service-drools-app/tree/master/emergency-service-taskslists-ui-web
And also there is some documentation here:
https://plugtree-org.ci.cloudbees.com/job/smart-tasks/lastSuccessfulBuild/artifact/smart-tasks-doc/target/docbkx/html/book.html
I will be publishing some more information about this in my blog soon.
Thanks!
Demian