So 888 not 666 gets it into DMX programming mode. Say you have a 3 channel fixture set to DMX ch 501 and you want to ulilize sliders 4,5 and 6 to control it.... Use the up/down buttons to set the dmx channel in the LED display to 501, then press the 4 flash button to set it. Then use the up botton to go to DMX 502, then press the 5 flash to set it. Then use up again to select 503 and press flash 6 to set the last channel. Then when you exit, those sliders are set for that fixture. Would have been great if someone would have corrected the manual and also explained the need to program dmx channel for a multi channel fixture, and not just the first address.