Thank you for the report!
Since you're peeking at the leftover / legacy texture paths it's an easy way to see what I'm doing here: Originally all these animations shared a texture folder that I was constantly updating (for performance). But I switched to having them be independent, to improve compatibility and ease of use.
Some of these references are hard to find because they're tucked inside the Advanced Render Settings tab, which has some branching textures in it. I thought I had squished most of these, but some still slipped. How do you get the missing texture report? This sounds like a very useful tool for debugging, as for me they just look like they work!
I'll upload a new update as soon as possible, fixing these leftovers. Thank you once more.