Hello,
Sorry to hear you are having issues. But, I just test this out and I have no issue on this. Upon first log into my second account. My Start button is on the left with the rest of pin apps next to it. But, Start11 ask me if I wanted my Startbutton to be in the center. Once I press yes. It centered itself. And now I am back on my main account. This one too in the Center.
Would like to suggest to do a purge and reinstall and see if that help.
Please try purge and reinstall steps as mentioned here: [link]. Just make sure to redownload the latest version from your account. Reboot after the purged. Reinstall, and Reboot again after the installation. Retest it. Report back here.
Basj,
Stardock Community Assistant.