Oops, I think I turned the random picture thing off on accident. haha thanks for pointing it out, I need to fix that.
But basically, doing things with photopost is very simple if you have any php/mysql knowledge. Basically, in the photopost database you have all of the data which point to pictures in the data directory. So, all you need to do is have some code to execute a MySQL query to collect the data you want (such as 3 most recent photos) and then use the php code to display the output in HTML.
That's what is great about photopost, is the way its setup and with the database it is easy to write code to get almost any kind of result you could want. The key is knowing how to code a little or knowing someone who does