If you find that your UWP or Windows Store apps are being blocked by Parental Control in Windows 10, then this post may be able to help you. Many users reported on Microsoft Answers that they were facing this problem on their Technical Preview version. One solution posted by a user there was found to help many. I am posting that solution below, hoping it helps you too.
Windows Store apps blocked by Parental Control
You may find that your Modern apps just do not run or even your Start Menu does not work. It is quite possible that your app activation is being blocked by Parental Control. If you open Event Viewer, you may be able to see this in the logs. It could be happening on your Admin user account or any Standard user account too.
To resolve this issue, open an elevated command prompt windows, type the following command and hit Enter:
ren %windir%\System32\AppLocker\Plugin*.* *.bak
Once the operation completes successfully, restart your Windows 10 computer and see if this has worked for you.
Some of you may want to have a look at this post which shows you how to re-register Windows Store Apps in Windows 8 and later.