can't print to my Okidata C5200n

I've reviewed previous forum posts, and can't figure this out.

I have a Mac Pro running the latest OSX.5.5, and I have a known good Okidata 5200n attached to the USB port. The Mac sees the printer, as that it correctly identifies it in the printer control panel.

1) I went and got the latest driver from Oki specifically made for 10.5 OS (OSX5C5200E.dmg).
2) I ran the installer, and followed the instructions.
3) It APPEARS to load, however, I can't find any new files that are written anywhere (including when I created a new "oki" directory on my desktop and loaded the driver specifically ONLY there... it created the directory, but the directory is empty).
4) Additionally, the driver does not show up in the driver list when I try to add the printer through the printer control panel.
5) The generic drivers aren't driving the printer.

How do I get the printer to work?

Sean