there are 3 LED related functions in the Check Point kernel ...
janus_pld_red_led_set (Bit 0x01)
janus_pld_yellow_led_set (Bit 0x02)
janus_pld_green_led_set (Bit 0x08)
they write to port 0x348 ... this seems to be the Altera MAX II chip (PLD) next to the diag display
btw: the PLD also monitors powersupply status
... and there are 4 LED related functions for 'Phalanx PLD' ...
phalanx_pld_red_led_set
phalanx_pld_yellow_led_set
phalanx_pld_green_led_set
phalanx_pld_disk_led_set *****
this might be the explanation for the 'missing' led on the frontpanel PCB (Bit 0x04 is assume)
hope this helps - sorry for the late reply ;)
/paketix