For build 3.0.0.201003152328:
On Windows 7 64-bit OS, drag and drop from control palette to xaml source view (at peoper place, not inside attribute) does not work. After dropping control in source view, the UI frezes for few seconds and donthing happens when UI gets activated.
Since the project is moved in eclipse, please report in eclipse http://bugs.eclipse.org/ unter the ESL project