>>> But others like installing aps are eluding me... eg I've downloaded >>> Firefox and double-clicked on the file to install it but it doesn't >>> do what I expect it to do... install on the drive... I don't know what you expect to happen, but what should happen is that when you double-click on the Firefox .dmg file that you've download a window opens which contains the Firefox icon. You *drag* the icon from that window to your system apps folder. It isn't *required* that you drag it to the apps folder -- actually, you can drag it to any location where you want want to keep it. That's all. . . . . . . . . . . . . . . . . . . . . . . O'Brien