Yeah, that works! 😄
Just one more thing: Some of the levels appear to be easier than they were intended due to the way Lemmings pass through the colour black (as this is the colour of the background). This appears to create space Lemmings can walk into that is perhaps not intended with this version, and certainly wasn't in the original game.
For example, when trying to rescue every Lemming for the gold star in Fun level 16 (Don't Do Anything Too Hasty) and not using blockers, I use the technique of mining down to the right then turning the miner into a bridge builder for a second to create a dead end trap. Then I do the same going the other way so I have two diagonal shafts that hold the lemmings in place, while the very first one builds bridges to the exit.
However, due to the bricks in the ground having small black (i.e. background) pixels in them, I don't need to mine the second tunnel. The Lemmings try to walk through the missing pixel and get turned around. This of course saves me resources AND makes the level easier to complete.
It's the same on the level Don't Let Your Eyes Deceive You: When they reach ground level, if you turn a lemming walking left into a climber, he won't climb back up the blocks they've just come down because there's a single black pixel in the block which he passes through and bumps his head.
I hope all this makes sense!
(Note that this doesn't happen with every black pixel - the trees in Best of a Level can be dug through, then the black parts walked across).