Well we are working on feature documentation for the product I can say that. For basic operation like upload procedure category creation etc basic operation use this http://www.photopost.com/manual/admin.html
There will never be a hacker's guide since code modification falls outside product support. We support our code as it is written. You may post in the mod forum to continue this discussion. You would specifically need to alter both your search.tmpl and search.php and showcat.tmpl files to achieve your hacking needs.