More thoughts ...
* I would like to start with downloading a PRADO "Portlet Edition".
* This would contain two pages (Home, Admin) and one component (TPortletAdmin), in addition to the framework itself.
* When I open index.php in my browser the Home.page shows up, with a login screen.
* After login I am at Admin.page, which contains TPortletAdmin.
* With TPortletAdmin I am able to scan the "Portlet Repository" and can manage portlets.
... so far, so good.
* Now I've scanned the repository and download for example the portlet XCssNaviagtion.
* A tar.gz package will be downloaded and extracted into a portlets directory.
* The newly created folder XCssNavigation will be added to namespaces in application.xml or a seperate file.
* Also there should show up a link, where I can access the admin options of the portlet. They could be stored in application.xml or application global-state for example.
Now, I should be able to use XCssNavigation in my templates.
That should be the basics. Did I forgot an important thing, or can we strip this even more?
When I take a look at my project phundament, I have a portlet called LContainer, which handles dynamic placement of components in the frontend, in my case called Cells & Bricks. In Symfony there are slots, I think, which do a similar thing.
That's a very important part, because I wanted highly dynamic layouts for content in the frontend. Together with the ability to create controls without coding.
So if there would be a system for dynamic content creation in the frontend, we could have a "Portlet edition" where you could build up your own application, just by clicking in your web browser

without editing a single line of code.
I think that PRADO users should have no problem with editing source code, but I would like to create a system, which is, as PRADO itself, made "out of itself", like in PRADO everything is extended from TComponent.