Just another Start11 bug to report!
I find that I cannot rearrange Taskbar program icons.
If I pin a new icon to the taskbar it is always added to the right side, if I unpin an existing icon and then re-pin it it's always on the right hand side.
The only way to fix this is to disable Sart11 from start-up, restart the PC, drag and drop the the icons into there correct order using the standard Windows 11 taskbar, then re-enable Start11 to start with Windows and either restart the PC or find the Start11.exe and run it.
Quite a nuisance really