Insert Product Blank Pages: The Case of the lower case
First off, if you have gotten this far into this particular thread, then let me say that Jason here has done a great job offline to help me. I wish to apologize for being so harsh earlier at the start. I always like a to eat a little crow with my humble pie. Sorry Jason and thanks for your time in trying to help me.
Anyway, Jason and I went over several possible causes for my problem and most worked but others didn't. However, to make a long story short, ultimately the fault was mine. I had made a copy of the image folder and did not realize that the original image folder was created with a CAPITAL "I" and mine was a lower case "i" (my standard, by-habit naming convention). Also, I had neglected to copy over the "Upload" folder for the images to go into.
After I noticed that small but critical situation and fixed it, and after some red herrings in setting folder/directory permissions on the host server and speculation about the .htaccess file settings, I set everything back to the default and was able to finally start adding products and images to the site.
There is still some question about the access settings being correct, but the thing is working now so I'm not going to mess with it too much.
The bottom line is, don't muck about in the files or directories more than what they instruct you. If you do, be prepared for the frustrating consequences as you go back and inspect any changes or renames you did in the process that could affect the function of your site as intended. All of my issues turned out to be caused by my messing with code I should have left alone or a simple (and stupid on my part) matter of a lower case "i" in a directory/folder name rather than a capital "I". That and a critical folder that did not get copied over caused me countless hours of frustration.
In my "real job" I deal with maintaining a state agency website and I thought I had it pretty well figured out, but we don't do a lot of PHP back end stuff like this and I took it for granted I could figure it out. I was too clever by half and it made way more work for myself than was needed.
I suspect if we just follow the directions as stated here would be a lot less issues posted on these forums. I just want to give folks a heads up on what the real problem with my issue was.
But I still have a lot of work to do before this site is fully functional as intended, but I'm feeling a bit more confident that I'll be able to get things sorted out. I'm sure I'll also be checking back here for more answers.