When you will be adding to a new model see the once I already added to see what I included.
Like Image, Game logo(used the same picture for image)

How to get Game logo
ex. http://gameblog.ucoz.com/stuff/action_arcade/duck_and_cover/1-1-0-5000
First you upload Image and add other details, but don't add Game logo you will do it later.
After you added your game go to the page of that game
on the right side you should see image 150 by about 109 , right click it and save it to your desktop
after you did that step go and edit the game you added and upload the Game logo using the image you saved it to your desktop.
Save it and your done.

Or you can just resize the image to the 150 by 112 and upload it as a Game logo, but I think it will take longer to do that.

P.S. Can your text be any smaller?!