Send the creator/owner of n-track an email. I believe it is flavio@n-track.com
If that don't work go here: http://n-track.com/feedback_form.html and fill that out. He very prompt with replies (one-two days, not bad considering he made the software and must be very busy)
But in my opinion I would say there are no plans for it. Now if it came out for Linux, that is what we are talking about
I asked the same question a couple of years ago when I first found N-Track. He has stated that he is not interested in programing for anything other than Windows.
It's a shame; there is a huge void in unix-based shareware audio for a program like N-Track to step in and take over OSX/Linux.
Keep an eye on Agnula ( http://www.agnula.org ).... they have started a RedHat/Debian system and say they will extend it to PowerPC architecture next.