[dnanian]

Sorry to hear that your old machine (I know, it's not really that old!) isn't as well supported as you'd like: it's a difficult situation, because we rely on the capabilities of reasonably modern OSX boxes...

In any case, you *can* use the Safety Clone, you just have to boot from a volume that is bootable -- a partition on the internal drive would work, for example.

Rather than trying to back up four volumes onto one -- something that'll make restoring very difficult -- why not create four parallel backup volumes on the external (and, perhaps, a fifth for just data)?