I’d like to know too, I started uploading some development stuff just to see how I get the high score API to work and now the delete option is mysteriously elusive….
So now I have a game to my name called “Bloop” with the description “doop”
If it isn’t published you can delete it with a ‘cancel upload’ link, when you view it. Counterintuitively, you need to have uploaded a swf to get to that stage.