I tried to point my new Beta 2 version of Moxie to the old Beta 1 workspace, and it froze on me several times. I tried using a new workspace and importing the projects with the same result.
The workaround is to build new project files on the old project directories (back them up if you're worried.) You'll have to re-set all your project properties, unfortunately.
I logged this as a bug - please vote for it here.