As far as I know, Windows 10 has a small known issue when the assigned Internet Explorer shortcut doesn’t appear after applying the XML layout file via GPO. To solve the problem, you need to edit the XML file and change the line for the IE shortcut as follows:
<start:DesktopApplicationTile Size="2x2" Column="2" Row="2" DesktopApplicationLinkPath="%ALLUSERSPROFILE%\Microsoft\Windows\Start Menu\Programs\Internet Explorer.lnk" />
And then through the GPO you need to copy the shortcut file “Internet Explorer.lnk” to the %ALLUSERSPROFILE%\Microsoft\Windows\Start Menu\Programs.
For the office apps, I consider that you could use <start:DesktopApplicationTile DesktopApplicationID=....
Check the xml file in the link below.
Also please check the sample LayoutModification.xml in this official website. I hope it will be helpful.
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