I gave up on all this garbage and got the old calc app back. Downloads / Software / Old Calculator for Windows 10 from Windows 7 or Windows 8 If I had a dollar for everything that MS broke with Win 10 I could buy a bunch of Apple stock.
Oh, the calculator is working fine on the RTM.
Try this with a Powershell with Admin:
Code:Add-AppxPackage -register "C:\Program Files\WindowsApps\Microsoft.WindowsCalculator_2015.914.10.0_neutral_~_8wekyb3d8bbwe\Appxmanifest.xml" -DisableDevelopmentMode
It's down to personal preference, I think the old calc is is easier on the eyes far less obtrusive than the new one. A big black rectangle clashes with my decor