There isn't really much to look at inside the GME I'm afraid

It has an editor:

http://i77.photobucket.com/albums/j4...lan/editor.png

A feed browser which helps when trying to determine element names for feeds you want to consume:

http://i77.photobucket.com/albums/j4...ed_browser.png

And finally the Sandbox for testing your applications:

http://i77.photobucket.com/albums/j4...an/sandbox.png

When you save your applications they are saved to Google Code (eg, Google Code) and when you publish the application it gets published to http://your-app-sub-domain.googlemashups.com. There are no other options at the moment.

Alan