Hello,
Sorry to hear you are having issues. Really not sure why you're having the issue with Start11. Start11 run just fine on my Windows 10 which also ran Start10 before. If you wish, you can try purge and reinstall steps as mentioned here: [link]. Just make sure to redownload the latest Start11 version from your account. Reboot after the purged. Reinstall, and Reboot again after the installation. Retest it. Report back here.
Thanks
Basj,
Stardock Community Assistant.