I want to load some textures and sounds off my server at runtime.
Can those assets in any way have urls that are relative to the webplayer (.unity) file? Or do I have to ascertain the absolute urls for them?
In the web player, relative urls should be possible, simply use URLs in the form "bla.jpg" (without any http:// or '/' characters) to reference a file called "bla.jpg" next to your unity3d file. This will not work in the editor, however (relative to what should it be anyways?), so you may put in some special code to prepend a hard-code file:// url when running in the editor for testing.