http://www.gcndevelopment.com/gnuradio/downloads.htm
The basic signal source/sink block examples are working fine. But I'm having trouble getting it to work with the RTL-SDR. Here is the simple flowgraph I tried making:

But running it just causes python to crash without much useful information:

Running the generated python script from the gnu radio command prompt has the same problem. Each time no useful error message is printed. If I click "debug" on the windows dialog, Visual Studio pops up with a little more information:

I have no idea what is causing this and would appreciate any input. The RTL-SDR is installed and plugged into the computer, working fine with all other SDR applications (SDR#, HDSDR, etc).