So it sounds like you are also having a problem connecting to your db right? We have some info that will help you establish your connection to the database from within Dreamweaver. On our new Web Development Workflow area we have this covered in part 4: Development. In here the first step lists how to create the connection to your db. Here is a link:
When it comes to the Digital File Pro problems you are experiencing please describe what settings you have in place that are allowing you to upload a file that is larger than the allowed size.