Ah, now I know what happened! My original IH4 install was incorrect! So IH4 did not actually install at that time. Zen Colorbox was installed after IH4 but that was BEFORE I corrected the IH4 install issue! I then found my IH4 install error which got IH4 installed. But this was AFTER Zen Colorbox was installed! And as I said right before this, I reinstalled Zen Colorbox one last time and that did indeed fix the issue. :)

In the interest of fully documenting this issue, I would like to address the contents of the readme files specifically.

I remember reading the below about Zen Lightbox in the IH4 readme....but I was not installing Zen Lightbox!

If you are using Fual Slimbox or Zen Lightbox with Image Handler4 you MUST read the "Misc" tab.
I did fully review both readme files. Neither readme file specifically mentions each other by name. IH4 is fully 100% clear on installing IH4 with Zen Lightbox per the quote above. I did finally find a reference in the Zen Colorbox credits saying that Zen Colorbox was based on Zen Lightbox but that is not mentioned anywhere else I could find. But this was not until AFTER the my installation. Would it not be prudent to add Zen Colorbox to the IH4 readme by name and vice versa? I am not sure it would have helped me with my issue. But I am sure that I will not be the only one to miss this important connection.

Thanks
Chris