Hello,
Sorry to hear you are having issues. But, do know Stardock do not support its product on Windows Insider Preview. However, I have forwarded your problem to Stardock Support Team for their review. We appreciate your feedback.

Basj,
Stardock Community Assistant

After the reinstall, and if it's still not working, go to 'Services' and see that the 'Stardock Start11' Service is running.  If it is not, open the properties for it and ensure it is set to 'Automatic' for its 'Startup type', reboot, and ensure it is still set that way (and the app is working). 

Sean Drohan
Stardock Product Lifecycle Manager

We do not offer support because the builds you are using are highly buggy and contain things which may never even ship.  Supporting that gets expensive fast.

Microsoft have been quite clear about this.  Do not use those builds unless you have a very good reason to and do not expect anyone to offer you support.  Without very expensive support contracts nobody sane will offer support on not even beta versions of Windows.

We have tested the build here and it is working on that insider build.  There are also no other reports of similar issues so it is likely the issue is a local installation issue or configuration one.

I would use the reset config option in Start11 (having backed it up first) as a test to see if that helps.