Windows TBB 3.0a4 "installs" - won't fully start

TBB 3.0a4 in Vista x64 hm prem SP2.  Downloaded a copy, checksum verified.

The "installer" runs, extracts all files (AFAICT).  By choosing either "run TBB now" or clicking the start tor browser.exe file, it only opens the border / frame of a browser window & a transparent browser pane.

"Tor Network Settings" shows on upper L corner of Nav bar.

Tor.exe 32 shows to be running in task mgr.  When click on the border of the empty browser, no throbber appears, as if it's through w/ any start process.

Uninstalled / reinstalled several times - no change.

Just extracting the files on this series doesn't seem to work. Extracts the files, but then can't start the browser exe file at all.

Trac:
Username: joebt