Pastebin with log excerpt: http://pastebin.com/1z4N4UMd

This happened after clicking the Space Center button while spectating a craft that someone else was controlling. The Loading screen appeared and KSP crashed.

Dev version: ecd4b58

Looks like it was caused by a null or 0 length file which shouldn't be happening. I'm closing this for now but if it pops up again I'll hunt it down ;)