Bit late, but anyway. My uncle gave me the game when I was about 3. I was unable to play it due to lack of a mouse though. A few months later my step-dad(he wasn't at the time, but he is now) gave me a Sega Master System and Lemmings for it, at first I found it quite hard and got my mum to beat most of the levels for me, but the time we were up to Tricky 14, I was completing levels myself. I guess it was about half a year before I finally beat the last level. About half way through, I also finally got a PC with a mouse, and was able to play on that too. I simply sped through both versions from there - fully completing the Sega version, and getting up to Save Me on the PC version. I eventually found a code to skip to the final level on the PC version, being unable to beat Save Me, and beat it easily. For years though, Save Me remained undefeated. I finally beat it about 2 years ago.
I also discovered LemEdit when I was around 7. I had heaps of fun playing around in it, and even more when I discovered the first Copycat Lemmings game. And then when I asked Peter Spada if making custom styles for it was possible, he referred me to Cheapo, which just set everything off.
After a while, the game just fell away and Commander Keen took it's place as my game of choice for level editing, but in 2003 Lemmings came back, and that's when I started actually releasing levels (starting with Lemmings Plus). Towards the end of that year, I lost interest in the game, and stopped playing. Then early this year, I rediscovered the game, and started work on a new pack - "Sunrise Challenge". However, I had so many level ideas, that I instead created Lemmings Plus 3 instead. (By the way: "Sunrise", "To The End!", "Into Eternity" and a few others were from Sunrise Challenge)