Sorry to hear about the ongoing drama with your XW mate. I'm not wholly familiar with your sitch, but is it fair to say your XW is a very difficult and angry person?
The school thing is grating for me, as it would be for you. If its something that would have been done if you were still together, let it go. If not, then raise it in the mediation.
Car seat - I think you should follow this up too. Its a safety issue, and may be unlawful where you are to have children that age travel unrestrained. Maybe have a look of incredulity and say something like "S7 told me she was riding without her booster seat. I didn't believe it as I know how cautious you are, but just thought I'd let you know what he told me". See what XW says.
CC - raise this at the financial advisor and follow up with an email. I'd look at a formal financial settlement and be done with the worry.
Good luck mate. Cheers, DS
Me: early 40's XW: nearly 50 T: 15 M: 5 BD: Jan 19 S:10 SS: 22 SD: 24
