This thread can be closed. Like I mentioned, I found a fix for it on that page:
You might have encountered with this strange and annoying error. This app can’t open for Built-in Administrator account please sign in with a different account and try again. or while User Account Control is turned off. You need to turn on UAC There is an easy solution for the error.
This app can't open for Built-in Administrator account
Solution for Windows 8 App Error:
◾Hold the Windows key + R and in run dialog box type: secpol.msc
◾Go to Local Policies –> Security Options –> Scroll down and find “User Access Control: Admin Approval Mode For built in…..”
◾Double click on it and select enabled and the press ok
◾Again press windows key and R and type regedit
◾Go to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\UIPI
◾And on the right hand side double click on default and change the value to 0×00000001(1) and click ok
◾Restart your computer and all the apps should work.