When I first launched it the black window appeared for about 5 seconds and then the “Sign in” screen appeared. After signing in it loads and runs with no delays.
Forgot about the HDMI driver install. It prompted me for the install and I selected “yes”.
I also uninstalled ET 3.0.5 from my Windows 7 PC prior to running any manually downloaded versions. Ran the Dropbox version as a portable.