Are you getting this msg when you submit Fanart?

quote

Fanart can only be submitted to a product that belongs to a series.
doesn't currently belong to any series. You may attach this product to a series by clicking here. Please contact our administrators if you'd like to submit a fan art for this product.

This has happened on more then one occasion, so if it ever happens again (like it is currently), fo find the forum of the game you want to submit your fan art to, through the Forum list. Once there, look at the top of the forum, where it says Profile.
Once there, you will find the "Fanart art" button, and then I think the rest looks familiar as always.

That way should work! ^^

Don't hesitate to PM LanDi or myself if you have any questions! =3

This just happened for another member; If you upload using this method, and you can't find the "Fanart" button, try a different forum of the series, it might work there. =3