Files
qt-creator/share/qtcreator/templates/wizards

Qt Creator custom wizards are located in this directory.

The subdirectories 'helloworld', 'listmodel' and 'scriptgeneratedproject'
are provided as examples.
To see how they work in Qt Creator, rename the 'wizard_sample.xml' files
to 'wizard.xml'.

The command line option -customwizard-verbose can be used to obtain
verbose information while loading the custom wizards.