I've been using my slingbox for more than a year. I use the Mac Slingplayer to watch TV (versus online at slingbox.com), and a few months back I was having that freezing issue.
The freezing issue is no longer the problem, but the screensize is all weird. I can't see all of the picture, for example, when I watch sports games, the scores at the top are cut off. Does anyone know how to resize it so I can see everything?
The other question is about the Mac Slingplayer? Is it still true that it is no longer being supported? I haven't updated my slingbox, and the website shows I need to update the firmware, but last I heard (back in January or so), doing so would mean I couldn't use the slingplayer anymore?
I see you're having some trouble with video size of your Slingbox. Have a look at this page, it will help you verify that everything is set up properly and should fix the issue.
Regarding the SlingPlayer Desktop for Mac, it is no longer being developed, however you can still use it. We recommend to use the Web-Based SlingPlayer so you can update the Slingbox and get new features.