I used an existing historical character last year, but yeah, I've taken it to mean that you can create a new past or future bearer... they just need to be the bearer of an existing Artifact.
The main reason that new characters were discouraged last year (and again this year) is because Top Cow would assume the rights to the character. And this is something a new creator might not be aware of or want. And, obviously, Top Cow doesn't want creators claiming that their characters have been stolen. This is why it has been made so clear.
Personally, I wouldn't use any characters that I've previously created and want to hold onto. But I would create a new character if I came up with one for a story set in the Top Cow Universe that demanded that a new character be created. I wouldn't be worried about Top Cow having the rights to such a character because I would've created said character for the Top Cow Universe.
I think they are referring to characters like Batman here. Like, say, if you were to write a Darkness/Batman crossover. That wouldn't be allowed. The stories need to be based on these characters (and by these 'characters' they mean bearers of the Artifacts, pre-existing or newly created), not other existing properties or entirely new properties.
So, you can create a new character if they are the bearer of an Artifact or a cyborg existing alongside Cyber Force but not an entirely new concept.
That would be my interpretation, anyway.
It says it's a twenty-two page script (although, this usually results in more actual pages being written as part of a word document).
I don't know if we're allowed multiple entries or not this year, although it has been allowed in previous years. If you're referring to a single entry, they'll only want the final finished document. Only submit it once, if you're unsure and think you might want to rewrite it, wait until the deadline to submit.
The Talent Hunt will run 10/15/14 to 03/15/15 (or 15/10/14 to 15/03/15, if you're British like I am
). That means we have until the 15th of March next year.