All of these things are doable - you would need to create some custom code to handle the processes.

And yep there is a very deep API which is basically the dotnetnuke framework to work with.

Westa

PS though - there is currently a limitation on the number of roles that DNN can handle which is attached to the fact that the roles are cached in a cookie.
you may need to be careful if you want roles being created all over the place.  - I seem to recall the limit is around 50 - but its not exact - it more relates to the limit of how much text can be stored in a single cookie - 1k comes to mind.