On Windows: Click Start->Run, and enter drwtsn32, click Ok in the next window, run Xonotic and wait for the crash. Then go to C:\Documents and Settings\All Users\Application Data\Microsoft\Dr Watson there should be a file called "drwtsn32.log", give that file along with the engine's build date to the developers. You'll see that date when you open the ingame console (How do I open the console?). Note that some folders of that path may be hidden or have a translated name if you're using a non-english windows.
On Windows: Click Start->Run, and enter drwtsn32, click Ok in the next window, run Xonotic and wait for the crash. Then go to C:\Documents and Settings\All Users\Application Data\Microsoft\Dr Watson there should be a file called "drwtsn32.log", give that file along with the engine's build date to the developers. You'll see that date when you open the ingame console (How do I open the console?). Note that some folders of that path may be hidden or have a translated name if you're using a non-english windows.