CapSense works well with LED backlighting. A hole can be made in the sensor pad. LEDs are available in a surface mount package that are designed for backlighting (LED shines light on to board). LED traces should be kept to the bottom side of the board. If more than one LED is mounted behind each button, ensure that the active sensing area of the button has not been negatively impacted by multiple backlight holes punched out of the board.