As I mentioned in my email, your right click menu on taskbar button look different on my windows. On yours it look like your "Close Windows" menu is missing. I am not sure if this is on Start10.

You can try these suggestion.
1) Make sure you have fully uninstalled ClassicShell since it might interfere with Start10.
2)Please try the following:
-For Win8/10 Users: Open the Start Screen, and type 'cmd'. Right-click on the search result and select 'Run as administrator' from below.
-Type: sfc /scannow
-Wait for the scan to complete (this can take several minutes)
Some help on how this looks should you need it:
https://support.microsoft.com/en-us/help/929833/use-the-system-file-checker-tool-to-repair-missing-or-corrupted-system
If the SFC finds errors, but cannot fix them, please also run the following command in the same command prompt window:
dism.exe /online /Cleanup-Image /RestoreHealth
Some help on how this looks should you need it:
https://www.windowscentral.com/how-use-dism-command-line-utility-repair-windows-10-image
The above command should assist with replacing any damaged or problematic system files. Please note, however, since it may require
restoring certain files, this process can take some time and you will need to be patient until it has completed.
Please let me know whether this resolves your problem or if you have any additional questions.
Thank you,
Basj,
Stardock Community Assistant