I do not believe that there is an inherent link between the two. Project Web Access and MS Project are made to go together and are a separate product. However if a user does not have PWA and MS Project 2007 is too much for a light project then the Project Workspace is the thing for that type of user. I was unable to find a way to link them, though there may be a way to do it using a program, but alas I am not a programmer.
JohnQTech