^ thanks for the tip but I'm already using Stuffit Expander (I think it comes bundled with Macs as standard).

The trouble isn't with the 'unstuffing' software, it's with the .sit file itself, which is corrupted.

In short:

1. I 'unstuff' the downloaded file, which itself contains a stuffit archive for each Poser character.
2. I 'unstuff' one (or any) of the character files and I get an installer file.
3. I double-click the installer and it tells me that the "file is incomplete" (or something like that).

Or even shorter still: damn!!

Like I said, I've tried contacting DAZ to get hold of a new (and uncorrupted) copy of the original file, but I ain't holding my breath. If I hear anything I'll post here in case any other Mac folk have the same problem.
.