UIPanel has a Refresh() function that will update everything immediately. Of course if the widgets were just activated, you may also need to panel.Broadcast("CreatePanel") first so that widgets add themselves correctly.
Every tool has a learning curve, Vertigus. If you don't like it and think your $47.50 will not save you time versus rolling your own UI solution, then by all means -- create your own. Make it all that you want it to be, then do support for it and face the criticism of others who each have their own opinion of how things should work. I'll give you a heads up though -- you can't please everyone, and you can't teach people who don't want to learn.