The customization wizard allows to adjust the currently loaded Disposition without need to get into jOrgan's details.
Dependent on the elements contained in your disposition several pages enable you to conveniently customize different aspects of your disposition:

Select a Midi device and transpose for each Keyboard. Channel, lowest and highest pitch can be set explicitely or recorded:

Select a Midi device to control all elements on the Console. Click on a table cell to record a message, if configured these are shown with a small yellow icon: Each time a matching message is received, the corresponding cell will be highlighted in yellow.

Some extensions support additional customization pages.