Thanks guys!
So I submitted the completed exercise, done in 2.82. I get the concept, I still can’t seem to translate it to 4.1 though. I tried clearing the keyframes using the method suggest by Dwane. I have “only Active Keying Set” enabled, I disabled all mods except a couple basic stock ones, and I still get that error when trying to insert keyframes between other keyframes using either “I” or “K’.
“K” gives me a keying set options menu. When I click any of them, it doesn’t give me an error, but it also doesn’t apply any keyframes.
I tried this same process in a new file, as well as with the “bouncing ball” blend file from the course files, and the same thing happens in both. I’ll include the video of the other basic animation. It’s just a weird shape spinning.
So as much as I dislike not solving errors, no this is not a major holdup. It could be somewhat inconvenient for my animation workflow, but at the end of the day I can work around it.