(I'm not sure if this is a bug or just a button that I switched on by accident) (sidestory) I was happily mapping for L4D2 using the Left 4 Dead 2 Authoring tools, without a worry. I closed it down, and starting playing another game besides anything Source based. After I while, I grew bored and continued mapping using the L4D2 AT. Though, something was wrong, and, very annoying: (problem) I tried to select a brush in the 3D camera zone. It worked just like it should. But then this happened; when I tried to select another brush, it didn't select that brush, but chose the brush/object/thing behind it, ignoring the brush I actually wanted to highlight/use. If however, nothing is behind the object, it chooses it the correct way. An illustration: How do I fix this problem? It's gone from L4D2 AT to Source SDK, and since I also map for TF2, this is relevant.