lego: nice work with the ENG fire... two things I've noticed:
1st there should be a light next to the eng master switch saying "FIRE"
2nd: on release of the fire test btn the sound should stop... (is a bit annoying to hear that sound until the apu is up, to cancle the warning
Another, unrelated thing:
the configuration warning should show up as well, it TO CONF btn is pressed and acft is not in to conf... (see DSC-31-15 P 5/6)