The error indicates your server is not sending dynamically generated javascript files to the client. There can be a number of reasons for it, from misconfigured web.config file (not likely if you are using a known working version of that file) to some kind of server misconfiguration.
I suggest searching the internet for 404 and ScriptResource.axd. You should find a number of hits by people with the same issue. When you figure it out, please post the answer to help the next person.
Roger Martin
Creator and Lead Developer of Gallery Server Pro