Hello NJHUK,
I think there are a couple of ways to address your concern.
- There's a chance that you've been changing settings in the wrong profile on account.microsoft.com/family.
- The settings that do apply to your daughter's tablet may not be correctly set
Here's why:
Previously, when you logged into familysafety.microsoft.com, you had a single line item for your child, and because you used Windows 8.1, that single entry also showed the MSA that was associated with her. It was a shared "view", but the initial setup was very manual and had to be done on each PC and the settings didn't roam. After the account unlinking this spring, the MSA entry that shows for your daughter has the message about logging into a Windows 10 or Windows Phone device, and the changes you make in that profile aren't getting pushed to her tablet (simply because it's not (yet) running Windows 10).
So let's start by making sure you're using the right profile:
On account.microsoft.com/family, look for the entry that shows her name and the tablet name and select it (i.e. not the entry that shows her MSA).
NOTE: If your daughter's tablet name doesn't show on the family page at all, you'll need to check to see if your daughter's account type on her tablet (PC settings/Accounts/Other Users) is set to something other than "child". If it shows as a standard user, please set it to child. If it happens to show as an administrator, or if it's the only account on the device, you'll need to add an adult's account as an administrator, and then change her account type to child. Once her account type is set correctly, click the "manage family safety settings online" link in the same window.
Once you've verified that you've got the right profile:
Navigate through every settings page that shows on the left side of the page and make sure they're set how you expect them to be. I was surprised that on one of my PC's I hadn't set the "block inappropriate web sites" setting correctly, and it was toggled to off. Also, be sure to scroll down on each page - there may be settings that show underneath.
In terms of kids' ability to get to content they have no business seeing/hearing, as long as the web filtering is set to on, then InPrivate browsing is disabled and SafeSearch is set to on by default. Those are things that really help me. Then if anything sneaks through, I also block individual websites. As for websites like YouTube, so much of that isn't rated at all, but I've used the kids safety setting on the website to help filter out what I can.