This project has given me the needed kick in the pants to finally try installing AviSynth on my Linux laptop under WINE, and I gotta say I'm likin' AviSynth already! Very cool.
Haven't tackled the encoding yet, but I can open the 3.09 AVS file in VirtualDubMod and step through frame by frame, albeit slowly.
Thanks again to dark_jedi for collecting the required filters in one place; however, I did have to download FFT3DFilter separately.
http://avisynth.org.ru/fft3dfilter/fft3dfilter211.zip
Was that line added to the script after dark_jedi uploaded the RAR? Or is it something peculiar with my WINE/Linux installation?