I just got a second-hand MX-500 (my first programmable universal remote).

I've successfully used the "learn" mode to emulate my Humax PVR controller, including setting text "Red/Green/Yellw/Blue" against four of the LED buttons.

BUT although I can change LED display text within each "Device" menu, I can't see how to change the LED text for the 10 different devices in the "Main" menu.

Because it's second-hand, the existing device names don't match the equipment I want to control. How do I edit those names?