Some controllers only handle 4 units, and you can select whether you control units 1-4 or 5-8, hence the 1/5, 2/6 and so on.

On my T2, I have various approaches. In my HOME page, the Channel + and - turn on / off the main HT lights with normal click, and the media library lamps (which are also in the HT) if held down. Additionally the "off" for the main HT lights will also turn off the media library lights.

On the X-10 device page, the LCD buttons are used for on and off macros for specific areas in my house, while the numeric pad is used to enter unit numbers, the left and right cursor buttons send the on / off commands, and the up and down cursor send the bright / dim commands.

DJ