Downloaded, configured, and installed on my Mac
over and over agan, it seems.
But it was not for naught: I finaly got the Landscape Change Thumbnails/Zoom script to process all 12,000 files.
The Zoomify part was a bug in the ZoomifyBase.py code. There was a line
tempImage = imageRow.resize((imageWidth/2, imageHeight/2), PIL.Image.ANTIALIAS)
well, if imageWidth or imageHeight was <=1, el bombo. Changed to
tempImage = imageRow.resize((halfWidth, halfHeight), PIL.Image.ANTIALIAS)
Much happier now