Is it possible as well as worth it to make kdenlive build with qt4mac-devel?
An additional question is there a way to make kdenlive build with ffmpeg-devel as well from a fresh build rather than building kdenlive conventionally and entering in "sudo port -n upgrade --force mlt"?

I have never tried qt4-mac-devel.
Re: ffmpeg-devel. Yes, simply install the ffmpeg-devel port before installing mlt or kdenlive.