Loss of Lemmings: Zero
Disable the trap trigger with a Filler. Rope from about 1.5 inches left of the gate to the corner of the steel. Fly a Super Lemming from this steel round to the top right house. Fence back to release the main horde. Position the cannon with 3 links of chain showing on the left. After one Lemming has been successfully launched onto the ramp, move the cannon. When it reaches the top, Fill the pit and Rope the gap. Reposition the cannon for the rest of the Lemmings. It will take some time for them all to get out.