Good news and slightly bummer-ific news:

JCS for Mac is ready, and I'm uploading it now! JJ2+ for Mac has one more issue left that needs ironing out, and I'll post it as soon as possible; could still be today, but might be another day or two.

I'll edit this post and the first post in the thread with download links as they become available! Stay patient for just a bit longer, and JJ2+ will be running on your Mac like syrup on a delicious waffle.

Edit: Download link!

JCS for Mac is ready to download - get to it, and put your shiny iMac to work making some great levels! The download comes in the form of a standard .dmg file. It's compressed, and weighs in at about 217 MB. Enjoy!
JCS for Mac, v1.00