When v2.55 was released, the older version no longer available for download. Try to look into your download directory to see if you have save the older version there.
Perhaps, The V2.55 was not installed properly. Would like to suggest doing this steps:
Please try, uninstall Start11, reboot immediately (important), download latest version available in your account product download page: https://store.stardock.com/myaccount/products. Install it, reboot immediately again. Retest it and report back.
Thank you,
Basj,
Stardock Community Assistant