I did have a Megaman level once, made for 1.23, but after I accidentally opened it in the TSF version of JCS it wouldn't work on 1.23. Go figure!
I spent about 1-2 weeks on this level.
Here's a screenshot I took months ago before I screwed it up:



This level was part of a 4 level pack called Mega Jackrabbit I was making about 6 months ago.