Hi Roberto,
We are working on a new 7.0.0 milestone that will keep focusing on the engines like in milestone 1. In the meantime we have released a Design application in the cloud for which you can signup for free and use that as a modeling environment (Model in the cloud | Flowable Design | Free). The open source UI applications of version 6 are using an outdated Angular 1 version, with lots of security issues etc. So that’s not something that we can continue in this way.
Best regards