Lot's of thing's were clarified and modularized of the API. From code reduction to bugfixes and further functionality added. I just want to say it works great. It's a kind of WYMIWYG (What You Mean Is What You Get) no magic has some caveats. Like latency of physics isn't clarified for now. May be some initial magic is needed and if you know Advanced Gtk+ Sequencer you know it's possible. It's strict layering and distinction of GUI, audio and thread interoperationality and meshing in a object orientated manner is one of the greatest advantages.