I had already ran the update before anyone had posted comments here and just never used it. Now that I decided to read the comments, I found the same issue. It came up first asking if I wanted the autoupdate and a "NO" answer says the app will quit. I chose to let it go automatically. Why? If not, then the app will quit so why bother asking? I think the developers at Logitech are smoking crack.

Anyway, after it fired up, I too got the same blank window. I closed it, checked the prefs, of which there isn't much there worth a darn. Then clicked over to my desktop, all while the Harmony software is still running. Then I clicked back to it, Harmony, from the Dock. The window appeared as I hoped and I clicked in it right away. I am not sure if that click, or just reselecting the windowless app, did the trick but I got the login screen and it seems to be working now.

I still agree with you all that this is the worst piece of software, ever! It is in no way user friendly, easy to use, flexible, fast, ... need I go on. Logitech used to be a Mac friendly company that had good products supported by the Mac. Lately, it seems as though, they have "given in" to the Bill Gates line of thinking that its all about money and who cares about everything else. So they promote the "Windows" environment and leave out the Mac. Funny as it seems, Microsoft has better Mac support than a lot of companies. I am a Microsoft "HATER" by the way.

Try out what I did and see if you get to use your software to program your remote once again. Hopefully Logitech will REDO this app to a real Mac app.