I am trying to load a resx file in my .net website using:
ResourceManager rm = new ResourceManager( \"Project.Resource\", Assembly.GetExecutingAssembly() );
I think the way you are using ResourceManager is wrong. See this post.
Also note, when you open Visual Studio command prompt, & run resgen.exe, it says its used to convert resource files from one format to another (i.e. resx to resources). I think, you will need to convert your file to resources from resx & then load it using resourceManager.