Cucumber-JVM is a pure Java implementation of Cucumber. You can run it with the tool of your choice.
Cucumber-JVM also integrates with all the popular Dependency Injection containers.
Please ask on The Cukes Google Group.
You can register bugs and feature requests in the Github Issue Tracker.
Please bear in mind that this project is almost entirely developed by volunteers. If you do not provide the implementation yourself (or pay someone to do it for you), the bug might never get fixed. If it is a serious bug, other people than you might care enough to provide a fix.
If you'd like to contribute to the documentation, checkout cucumber/docs.cucumber.io otherwise see our CONTRIBUTING.md.