We have uploaded a new version of the Activiti Designer (0.5.1) to the update site at http://www.activiti.org/designer/update. This new version now generates BPMN 2.0 XML and a unit test compatible with Activiti RC1. For the GA release we plan to include much more functionality in the designer. If you have requests please feel free to drop a post here.
You may run into a problem when installing the designer because of slow response of the Eclipse update sites. This can be solved by unchecking the "Contact all update sites during install to find required software".
