after I reinstalled Windows recently (Win 8.1 pro, 64bit), I also did a reinstallation of Robohelp 11.
The installation completed without any problems. When I start the application, it ask me to register. Afterwards I have to enter my Adobe ID and passwort, and then a window with the EULA appeards. A click on the "accept"-button closes the window and the application quits without any further message. I even installed the 11.0.1 patch, but this doesn't help too.