You just updated to 10.1.2 from what? I think the last update for 10.1 is 10.1.5 which you should update to! I'm also aware the very 1st Safari version had some bugs in it. But Safari is the recommended browser to use for downlding LW for OSX. It means you have downlded an incomplete dmg & OSX doesn't recognise what it is. eg: say the downld size should be 5.5 MB, yours is probably a little smaller at 5.3 MB or something (I've just taken those figures outta my head as an example!) This issue also happened to me.