Using Dreamweaver CS6.0.1 on Mac Mountain Lion 10.8.2. When I open the "Manage Sites" dialog box, certain parts of the box are not visible unless I wave or click my mouse on that portion of the screen. Really sick of this. Also text entry into design view in Dreamweaver is maddeningly slow. I've got a fast Mac Pro with an SSD and 48 GB of RAM. Seriously would like to find the answers to these problems.
I have Dreamweaver CS6 on a MacBook Air with 4GB of RAM running OS X 10.8.2, and don't experience the problems you relate. However, there are some people on Macs who have been experiencing problems with 100% CPU and slow typing. Apparently these problems have been fixed in the Creative Cloud 12.1 update. If you're not a Creative Cloud subscriber, a fix should be coming shortly. See http://forums.adobe.com/thread/1100065.
Thanks, David. I am a Creative Cloud subscriber, which makes my problems all the more disappointing. Dreamweaver has had FTP problems for more than a decade now. It continues to get slower and slower. Illustrator is pure bloatware compared to Freehand. Adobe has lost its way.
If you're a Creative Cloud subscriber, have you installed the 12.1 update? You can check whether you have it installed by selecting Dreamweaver > About Dreamweaver. It should say Version 12.1 Build 5949.
If you have a different version, you can update by selecting Help > Updates.
In that case, it sounds as though there might be something on your system that causing a conflict. I suggest that you file a detailed bug report through the form at http://adobe.ly/DWBug. Give details of what's happening and steps to reproduce the problem. Also give details of your computer setup and any other programs that are running at the same time.
Finally solved my problem after a year and a half of trying. The solution is here:
The Verdana font was not activated. I activated it using Font Book and poof, all my problems went away.