I just installed SP v4.20 from the DIR-827 site on OSX 10.7.3 connected to a DIR-655 and a LaserJet printer successfully.
The SP sw is not 64bit compatible from what I can tell. If you restart your Mac while holding down the 3 and 2 numeric keys on boot up, this will start the mac in 32 bit mode. Then run the SP installer. After it installs let it restart the Mac and this time don't hold the 3 and 2 keys. Just let it restart normally. SP should connect.
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