Slim went offline when you posted this and is currently at school, at least I assume as much, as he said hes has school today at 6AM. I'm sure he will respond to this as soon as possible, but I may be able to answer your question.
http://www.tinyurl.com/graaluploading
This is the official Graal Uploading website, and has their rules posted twice on the page, both slightly different.
The following has been copied directly from the Graal Uploading website.
From rule breakdown:
From detailed rule list:
So yes, go ahead and make anything you want, however you will have to wait until they allow the uploading for it. Having something made ahead of time is always nice because you can just go ahead and email the file to classic@graalonline.com when uploading for other pictures is allowed. Therefore, getting your picture uploaded before most other people, so less wait time.
