SO very glad I'm not the only one with this seemingly EXACT same issue.
Photoshop CS6 via Creative Cloud membership.
Windows 7 Home Premium
Select > Color Range used to work perfectly before update 13.1.1
Now since the update 13.1.1 Color Range doesn't do jack properly. Selecting any color doesn't do anything. sometimes if I select a white it will act as though I've pulled out a gray.. but even one pixel difference will make it deselect. This only happens with Sampled Colors. All otehr color range preselections work as advertised. This would be great if I didn't need the precision afforded to me with Sampled Colors. This is mission critical to my daily work as a scren printing artist and have been unable to find a succesful workaround.
Is there at least a way (without having to uninstall/reinstall) to downgrade back to 13.0.x until this bug is found and fixed?
At least for me. All I did was trash the Preferences file and now Color Range works as it should. You may possibly have the same luck.
Scott, thank you for posting back here. Yes, it worked for me too. And now I'm very pleased.
Very glad it worked for you too, hopefully this will help others who have the same issue as well.