Am very pleased to report that WindowBlinds works great with the Windows 10 Tech Preview.
Upgraded from Win8.1, rebooted, and WindowBlinds works fine -- no problems.
I did have to uninstall both Start8 and ModernMix, but I expected it would come to that (in the short run)
UPDATE: Please NOTE: Windowsblinds does NOT work with the Released version of Win10! As mentioned in numerous threads, if you force the install of Windowblinds on Win 10 now, you will have problems as a result.