I took a peek in the script and saw the comment about tips. What exactly is the problem you are having with it? I managed to swap the character text, image and icons and can control what characters show up on the tips screen at any given time. See: https://imgur.com/a/0WxyWXB
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Oh wow, I wrote that comment literally over two years ago, I didn't expect someone to actually respond to it! It's been a long time since I tried to wrangle the tips code but I remember my main difficulty was in getting the new assets (button, sprite, description) to show up without simply replacing the existing ones.
If you have Discord, could you hit me up at "it_is_erin" to go over your process for this? I'd be immeasurably grateful for the help!