It looks that this error comes from a problem in your .exe or associated data. Sometimes, rebuilding it should be ok. If you use a ftp to download it, zip it and change the name of the extension (exemple .blah ;) ) to transfer your file, then rename it correctly and extrat the files. It worked for me !
More informations here : http://forum.unity3d.com/threads/38135-Error-Could-not-preload-global-game-manager-0
answered May 16 '11 at 03:31 PM