The title of the thread is 'Downloading Games' which might supposed to be 'Submitting Games'. The submission form has a field for the dimensions of the game file. The description of Dimensions are there right under the field, it has to be in pixels. If you created a game, i would assume you know the dimensions of the file, though I have no clue about making games.
And if this answer is totally off, I apologize, but you have to be more specific when making threads.
Obviously DM, he was talking about this. But a real game maker would: 1) Know that it's not called "downloading" as you're doing the contrary (uploading). 2) Understand what "game dimensions". i'm not a flash developer but I think it's for the size of the "board" of the animation. For example 10cm on 10...
I'm not sure about it though.
Oh, and if you submit games, make sure you made them before