Nothing seems to change when I register
Please see all the docs available from the link above.

Nothing will change in your copy of ChurchBells until you put in the permanent code.  Codes are machine dependent.  In other words, each full license code is personalized to your own machine, since it is based upon a demo code that is personalized to your own machine.  You get us the demo code and we get the permanent code to you and you put it in.

But supposing you DID put in the permanent code:
You will still have to click through the license screen when you launch ChurchBells; this keeps the "kiddie fingers out of the cake", and alerts an heir of the tower project to licensing issues.

ChurchBells music is not like normal music where you buy a record and you can play it anywhere for minor royalties.  I had to be careful when setting up the licensing, to keep clever attorneys from unraveling my rights like a sweater.  So some precedents had to be established and maintained.

Therefore the "overall look" will be the same: a license screen to click through when you "pop the hood" to work on the engine of the car, so to speak: in other words, when you start to program the custom schedules.  Although licensing does not automatically increase the number of tunes in ChurchBells, it is still a necessary step toward getting extra tunes into use.  When ChurchBells starts, it mounts for use any sound files it finds in the ChurchBells directory.  You might add additional hymns you played with your own bell choir or carillon at your church.  But to get them scheduled means that you need to create a custom schedule.  That's where having the Organizational License comes in, in a logistical way.  Furthermore, only the Oganization Level license legally allows you to play the bell tunes outdoors.  So there is both a practical and a legal advantage to having the license.