Never had to do that. Weird thing is now I have 2 start buttons. The center one from win11 and the original to the left on task bar. Tried to relocate the center one to the left, but it overlapped the original one which was a pita. I'm not happy with the shortcuts in the center looking like a linux distro. Can't find a way to delete/unpin the center start button either.
I'll upload my custom .png. You can select it as an alternate start button. It covers the new one almost entirely (at least on my surface screen, which is some weird 2K or 3K format). You could resize it if needed.
Also, I was able to move the taskbar icon over to the center. I'll see if I can find the setting and screenshot it for you.
The one thing I'm really find annoying is when I go to shut down if there is an update, the options are on my menu to install updates and either restart or shut down, and also plain restart or shutdown without updating. However with Win 11 and Open Shell, when I select plain shutdown, it updates anyway.