I'm using 4.3 since it's out.
About changing the interval, I guess I wouldn't help you because, as I said it happens after a couple of hours. In fact, I can't stay in front of my computer and wait for the crash.
I use to let my computer works night and day; and when I come back in the morning, there's no more LS.
All I can say is that without LSMail, no crash even after three or four days running (until I need to have admin rights again and logoff)
I'm thinking about doing without LSMail because Litestep do some works for me. Sorry