[2013-07-13 20:08:26] Disabling extra threads due to dynamic mode.
I'm assuming your talking about dynamic mode?
If so it's not an error. Dynamic mode adjusts your GPU in an attempt to keep your desktop GUI responsive so you can use your computer while mining. Dynamic mode only uses one thread instead of the default 2 so it's disabling the unused one.
--intensity|-I <arg> Intensity of GPU scanning (d or -10 -> 10, default: d to maintain desktop interactivity)