Here are some basic SEO steps.

Keyword research.
On page optimization like keywords in title and meta tags and description and the content itself.
Measuring the keyword weight. So as not to make it more or your site will considered as spamming keywords. Not too less or your competitors will be on the top.

Do more keyword research and try to target multiple keywords from the inner pages.

The script itself also needs to be having SEO friendly URL's and all that stuff.

If it can generate dynamic sitemaps then good or we can generate manually and will have to submit it.

Now of course the off page optimizations like.
- Press release.
- Directory submissions.
- Article posting.
- Social Bookmarking.
- Relevant links exchange with other webmasters.
- If you are a frequent visitor of forums then some forum posting to get the word out.
- If you own any blogs then some blog posts and reviews about the site.

The above steps will help you to optimize your site and get better rankings in the search engines.