Oops - the change so that 'alt' stops snapping in the layout view accidentally assumes that a layout view is always visible. It shouldn't crash if you have a layout open, but it does crash if one isn't open. It's fixed in the next build.
I don't think we'll issue a quick fix for this. Builds can be pretty time consuming sometimes, and problems are to be expected in beta releases. If it's a big deal for you, roll back to r134 for the time being (or try to remember not to press alt :P)