O.K. I got it now. I am now able to capture the array of colors that I need. It appears that the "Comment = ... " array was changed at one point, and my script was set up to read and parse it the old way. I rewrote the script to use Anthony's "-format %c histogram:info:" method, and now I am back in business.
As a final comment, I would like to just thank everyone involved for the terrific support and for this terrific application. It never ceases to amaze me that the open source world flourishes as it does, based on the generosity and genius of the developers who manage and support projects like this. Your work has meant a lot to my own efforts, and it has made it possible for many others like myself to afford high quality products. It is all quite inspiring.