[dnanian]

Well, the "(null)" is because OSX is throwing an exception when we ask the system for the list of drives. That may indicate a problem with an attached volume (peripheral or network).

The beachballs are nearly always due to either a slow responding device or 'prebinding' issues. Try powering off your Mac, holding down Shift and powering on, with Shift down. Keep it down to the desktop, then start SD. Better?