Quote - o.k., got it. alpha gain fades tracks in-n-out using their alpha channels (masks). that covers all three colour channels, however, in qt pro, which is a cheap video editor I use to do gifanimations. i'll check out pd pro, see if there's an OS X version.

alas there is no OSX version, but it does run on a MacIntel core-2 duo systems with either dual boot (boot camp) or with Parallels in which case you can use other windows CDs to boot into WIndows while MacOS is still running.