I just uninstalled the last beta and installed the Win64 release. The first strange thing was that that the desktop icon was not created, even though I checked the option. Then Scrivener froze on the ProjectTemplates screen and never got past. Multiple uninstalls, reinstalls, manual removal of old directories, manual cleanup of the registry, completely shutting down Kaspersky, nothing changed the outcome. The only idea I have left is that Scrivener 3 just doesn't run on Windows 7. Does it?
The tech specs for Scrivener say it should run under Windows 7, as long as you have service pack 1 or later installed, and have the .Net Framework version 4.6.2 or later installed. Does you computer meet those requirements?