French language Q&A Forum

I didn't know what else to title my question/issue around this particular subject, but it seems that there's a lack of consistency even here on Kwiziq concerning this subject, evident because of the questions & answers here. There's a "fill-in-the-blanks" exercice that I just revisited titled "Voyage autour du monde" (https://progress.lawlessfrench.com/my-languages/french/tests/overview/1544705) that has two answers which contradict the lesson and feedback.

"Je visiterais d'abord la Californie, puis j'irais en Arizona." According to the lesson, and feedback the correct responses should be "Je visiterais d'abord en Californie, puis j'irais dans l'Arizona." 

Ergo: Confusion Leads to Confusion. 

So, the lesson on combining nouns says to use some form of à when describing a taste and the lesson gives the example of "glace à la vanille."  That seems consistent with my memory of "pain au chocolat."  So why is it "les œufs en chocolat" and not "au chocolat"?  Thanks.

The question is make "Elle s'est maquillée" negative. The following two responses each have a spelling mistake but one is considered "nearly right" and the other is considered incorrect. The answers are "S'est-elle maquillee" and "S'est-elle maquillé". I don't see the difference in the context of the question! Why aren't both "nearly right"?