Two questions

Hi! So I just got a batch out and I had two not so good surprises.

First of all my purple turned pink, which I kind of expected but hope it wouldn’t. What purple do you use to get a nice purple and not other colors?

Second question, I did a petri style set but the white just really sank down, and didn’t cure. It was a sinking white. As soon as i pour it in the mold I knew something was wrong, so I did try to use another white which I think was right but that didn’t sink at all and isn’t visible in the dice. What did I do wrong here?