Can this product be used with the internal sensors of the monitor to perform the calibration, or does it require the use of an external sensor?
This is just the software application that analyzes the data coming form the sensors. However, there is no possibility to use the built-in sensors. You will actually need the cable/external sensors or the software won't have anything to analyze and check. For more information, I would like to recommend you to visit the official website where more details are given for this product and software.