Hmm. I may be able to offer a little advice.

You mentioned that this is your first go at a computer map. Have you already done a map of this area using pen and paper? I've found that when doing maps, it can be helpful to remind myself what I'm going for. Otherwise, it's way too easy to get lost in the details. If you can post a pen and paper sketch, we can see not just what you have, but what you want. I know I'd love to see what you're going for!