Powershell – Error repairing Exchange 2016 install on Windows 10

I am trying to install Exchange 2016 CU6 on my Windows 10 machine (management tools only), but when I run the CU6 installer, nothing happens at all (splash screen appears, then disappears and no further dialogues or error messages).

When I went to repair my CU1 installation, it says it has detected an incomplete installation and needs to try and complete it. After attempting to do so, it fails with this error:

Error:
The following error was generated when "$error.Clear(); 
          $roleList = $RoleRoles.Replace('Role','').Split(',');

          if($roleList -contains 'LanguagePacks')
          {
            & $RoleBinPath\ServiceControl.ps1 Save
            & $RoleBinPath\ServiceControl.ps1 DisableServices $roleList;
            & $RoleBinPath\ServiceControl.ps1 Stop $roleList;

          };
        " was run: "Microsoft.PowerShell.Commands.ServiceCommandException: 
        Service 'Application Identity (AppIDSvc)' cannot be configured due to the 
        following error: Access is denied ---> System.ComponentModel.Win32Exception: 
        Access is denied
   --- End of inner exception stack trace ---".

Can anyone advise how I go about repairing this install, so that I can either fully remove it and start over, or try the CU6 installer again to complete the update?

I found this link where someone edits one of the install scripts to exclude the AppIDSvc which allowed them to continue with a 2013 install, but that obviously shouldn't be something you do. I am hoping there may be a clean supported way around this.