Here's my 100% solution in wingdings:
Block the first lemming when he almost reaches the bubble pit.
Let one lem climb up the left pipe and also make him a floater.
Let the lemming fall and go towards the trap (it doesn't work) and let him climb up the next wall.In the meantime free the blocker with a miner and set the RR to 99.
Then the climber climbs another pipe and hits his head,make him build to the right so he reaches the platform.Make him bash and go up the top pipe.
When the lemming is almost above the exit,make him dig down,fall and dig down again about 6 pixels,make him build to turn around and when he turned around,make him mine down and when he's just a little below the level where the other lems are trapped,make him bash.The basher must stop when he reaches the other lems,but should be below them a few pixels or one lem will drown.
As all the lemmings go towards the exit,the climber climbs up the pit but hits his head and also goes into the exit.
100% saved.
