I use all the customizations (Open Shell, Explorer Patcher, 8gadgetpack, Winaero old calculator etc) to make Windows 11 look like earlier Windows (Windows 7 gadgets, Windows Media Center, start button and start menu, Windows 8.1 system icons, Windows 10 taskbar right-click menu and recently Windows 11 21H2 style Task Manager). Never had any issue. If you apply each patch carefully you shouldn't have any issue. I recommend enabling System Restore (disabled by default) and create a restore point before every patch. If you encounter any problems just return to the latest restore point and try again. If the issue persists please post so others know what to avoid.