Using DME from Märzen Kit For Starter

[DukeWashterbuckle]

I recently ordered a märzen kit from Northern Brewer (which hasn't arrived yet) and will be making my first attempt at a lager. I decided that making a starter would probably be a Good Thing due to the need for lower ester production. Unfortunately, I didn't order any DME apart from the kit. So what I'm wondering is, can I get away with using the DME included in the kit to make a starter? If so, should I cold crash it and pour the wort off of the yeast cake? Or will that just yield off-tasting beer? Since its liquid yeast, should I just smack it and throw it in? Any answer would be greatly appreciated! Thanks in advance.