To edit a key, it must be selected in the keyboard preview. The properties are then displayed in the lower area.
The width and height of a key can be defined. Changes are immediately displayed in the keyboard preview. To assign a function to one of the six actions, it is selected. The function dialog opens, whose description can be found here.
For frequently pressed keys has been found (eg spacebar, delete), the hit rates are very high. Therefore, it is also possible for individual keys to define the safe tip range deviating from the design.
New buttons can be added via the plus icon. The deletion of keys is performed with the trashcan icon. To move the position of a key, the movement must first be unlocked by the corresponding icon. It is also possible to exchange the functions of two keys - also for this purpose the exchange must first be unlocked via the icon. The locks prevent accidental moving.
On the tab "Test" the keyboards can be tried out. The fields require different input types (text, uppercase text, numeric, password).
A list of all functions can be found here