When your project is running and you decide to stop it, you will be able to download the already rendered frames (if any).
The % of progress displayed depends on the number of frames already rendered. As each node renders one frame, if each frame takes 30 minutes to render, it is normal that the display stays at 0% for 30 minutes. The % will rise as soon as the first frames are rendered.
Please note that several projects can run at the same time if their total number of frames does not exceed the number of available render nodes. For instance, if 400 nodes are available, 4 projects of 100 frames each can run simultaneously, since each node renders one frame.
The RANCH offers you a very handy feature for checking visually your animation project when it is being rendered. It displays 256-pixel wide thumbnails of a large sample of rendered frames on a web page specific to your inprogress project. To access this page, you just have to click on the Preview button which appears when your project is being rendered (and of course if there is something to preview: if each frame of your animation takes 30 minutes to render, obviously, there will be nothing to see during the first 30 minutes :)
Below is an example of what you will be able to see when you click on Preview (the preview image is always around 1900 pixels wide, its height depends on the number of thumbnails).