I totally agree with your comment! It was my intention to display results after the dice have been modified, but unfortunately I didn't have time to implement that. Good idea giving time to players to look at the wrong solutions: I don't think I will directly change that in a future update, but I'll try to balance this idea with making things more clear, like with adding the modified results.
When you get a puzzle wrong, dice should always return to blank bbbuttt... a damn visual bug happens in a couple of levels and I hate it. I just didn't catch it when coding since I haven't playtest that much. I think that is the most confusing bit currently, since it's unconsistent and doesn't help players to understand what's happening.
Btw, you surely took a good approach by testing things out and I think that's a good thing for the game and I will try to keep it. By making it more consistent it will surely become more accessible, and the players will be able to understand that, in fact, the order of operation is the traditional one: x and % first, then + and -.
Sorry for the long response, it's almost a devlog now haha! I have actually already implemented these changes in the game project and as soon as the jam ends I will update the new version of the game. Thank you a lot for the spot on comment!