There is plenty of documentation. As mentioned its mostly done through the applications help function or the installer usually puts the in D:\Micros\Help\ and D:\Micros\Documentation\Help
However the basic steps are:
1. Open Pos Configurator
2. Devices -> Touchscreens (NOTE: NOT TOUCHSCREEN DESIGNER)
3. Add a new touchscreen, give it a name and choose the template. The template defines the resultion, number of buttons, location of buttons and check detail etc.
4. Save and close touchscreens window.
5. Devices -> Touchscreen Designer
6. From the drop down list choose the touchscreen you just created.
7. Add required buttons etc.
8. Modify some other touchscreen to link to the new touchscreen.
9. Done!!
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