Hi Marucio! Yes, I'm project lead for that eclipse project. and yes, I can use all the help I can get.
To get started, visit the project website and grab the code from git here:
https://git.eclipse.org/c/bpmn2-modeler/org.eclipse.bpmn2-modeler.git/
Because of breaking changes in the graphiti API (from graphiti 0.7.3 for helios to 0.8.1 for indigo) and EMF (2,6,1 vs 2.7.0), this currently only builds on eclipse 3.7 (indigo). I'm currently looking into how we can fix this.
Let me know if you need more info to get started.
Cheers!
Bob