Yes, this is commonly done in the games industry. And the whole idea of skinable/themed applications is becoming more prevelent everywhere else also (windows media player, winamp, netscape).

While we don't plan on letting customers make their own skins/graphics/themes for the interface we do need multiple themes.

Now as to your suggestion, to be honest you lost me, hehe. What do you mean by one steam?

My knowledge on how to create a theme is limited to the applications I have worked with that have themes (those listed above). In each of these the images are simply placed in a zip file. Each image must conform to a set standard (ie, the name and height and width must follow exact guildlines). Once zipped up and put in the proper place the program simply reads them from the zipped archive. Were you explaining this method or a different one?

Thank,
Bryan Smith