I've been encountering a lot of crashing with the latest K-Lite and I've been reading the boards a bit and it seems like a few others have as well. Well, I've figured out the problem. The thing that's causing all the trouble is the built in "speedup" clone, "Kazap". You need to pause this guy if you're crashing a lot, I assume this would only happen if you're downloading and/or sharing a lot of files.
I tested my theory, I could only run the program for about 4 minutes then it would crash (Yes, I literally timed it) and with KaZap paused (or "turned off") it hasnt crashed since.
I havent tried using the original Speedup, anyone is willing to continue my research...I might get around to it tommorow, who knows.
Anyways, try it and tell me if it works and especially if it doesnt work for you.