Took me way longer than it should, given I'm a technical artist for a game company. :-)
But the key is that when you upload the Web Page Inform 7 kicks out as a pre-zipped folder, you have to tell itch.io, in the options when you upload, "This file will be played in a browser."
Once you click that, other options open up that allow you to make the specified changes shown in that post.
And I'm not overly happy with the format of the embedded browser window, but at least it works now! However, I just noticed that there is a very grayed-out full-screen button on bottom that solves a lot of these issues.
I also took the advice to replace the index.html file with play.htm.
Deleting the original index.html, and renaming play.html helps too, since my ITCH color settings were not allowing me to set the colors on the actual browser page so my text showed up better. But now when you hit PLAY it goes directly to play.html which is preferable.
Thank you so much!!! Even the smallest barrier to play is a hindrance no one needs.
Sean.