I suppose the page doesn't really say how to start, though if you are familiar with servlets (which themselves aren't particularly complicated) then it should seem somewhat familiar. OTOH, I am not saying that you should use this instead of a full-stack system, and I'm not offering it up as an alternative to Django, and if you need guidance in application design this probably isn't the framework for you. Wareweb is a simple and predictable core, but it's only part of a full stack.
I could point you to the Commentary application I wrote, but I'm not sure it's going to help. And the Filebrowser app also uses it, but similarly it is a little funny and minimal (though at least it uses templates, where the Commentary application is so light on HTML that I opted not to use templates).