Duh! <slaps self twice lightly on the head> It seems like it was a long time ago in a galaxy far far away that I ran into this problem in a different context, but it was more likely in the last 3 years and I’d just forgotten that tidbit!
Moral of the story:
When you need the url of an actual image, do NOT try to use the url that Google Drive, Google+, or Google Photos gives you when you ask for a “link to share”! It’s not really a link to a photo! Rather, it’s a link to Google, feeding their cryptic image identifier to their viewer program
NOT suitable for the “ImageUrl” field in a component!
So, after exploring the discussion threads on a few Google user forums, I managed to track down an ACTUAL url for my photo. It was through picassaweb.google.com. I saw my photo instantly, clicked on it, it appeared in the Picassa viewer, right clicked the image again and opened a new tab, looked at the url, it was REALLY long, but it ended in .jpg. Copy THAT url and try in my component …
At first, it looked like it wasn’t working, but then it popped up. Success!! Take a closer look …
Yep, it’s the photo, but it’s WAY too small to show the detail I want. And the photo doesn’t resize even if I force the Component Options box to be very wide and very tall. So, while this solved the issue I was experiencing, it didn’t succeed fulfilling my goal: including a good diagram in the Component Options box to help the user select which size of angle iron they want to use.
Late last night, I was going through the one of the SketchUp sites - might be the blog - and I ran across a YouTube Playist: Making a Great 3D Warehouse Model … wait … quickly review the included videos … no, that wasn’t it, but it IS a great guide to creating clean, friendly and compact NON dynamic components, so it’s still worth watching.
So now I can’t remember (and correctly attribute) the next thing I think I’ll try: Putting a snippet of html in the Description field in the wrapper component attributes … I’ll probably report my success (knock on wood) through creating a NEW topic by replying “as a linked topic”
So Thank you @quantj, your correct answer to my stated problem has started me down a new path that holds promise!