Thanks for the links...

Now, I've got to handle (for now) one type of scripts. What they need to do is a couple of file operations (create some empty dir, check some file for existence, etc... nothing fancy), and then start a new process with certain arguments. So, that's kind of worked out with all that's already discussed, but there's another issue: it'll be good to have each script to set up its own UI elements in a more general dialog from the application.

I've only worked with non-scripts plugins in qt... and they handle themselves quite differently, obviously. If I were using this kind of plugins, I'd probably just do something like the setupUi function from the qt designer generated files, and have a slot I can call from the main app to start the process that the plugin represents (all the other stuff would be handled from the script itself and the generated UI). So when the app starts, I load every plugin, execute setupUi(some_container), and later on trigger the execute slot; after that the plugin will handle all the UI signals that correspond to it.
How can I port this idea to a plugin implemented with qtscript?