Couple of things: Did you create a new printer with the updates? I took a look at the power rip site and they said:
Please Note: Version 7.29, listed here for download, is for Mac OS 10.4 Tiger, 10.3, Panther and OS 10.2, Jaguar. PowerRIP X version 7.26 for Tiger/Panther/Jaguar is a free update to existing PowerRIP X users. All users with Tiger or Panther or Jaguar machines in their workgroups should download and install this update. Delete your existing printer and recreate it after the download.
Add a USB printer connection with PowerRIP X on 10.5 with 7.52 update:
Turn your printer on.
Open the "Print & Fax" found in the System preferences
In the Printer List window click the plus sign "+" under the list of printers.
Choose your "Default" for USB printers or "Appletalk" for Epson Appletalk cards prior to the 4800 printer
In the "Name" window, slightly change the name to be unique, perhaps add "RIP" to the front of it.
Go to the "Print Using" window and select "iProof PowerRIP X"
Skip the "Location" window, unless you need to tell others the printer's location in the building
In "Print Using" choose "Select a driver to use". Now type "power" next to the magnifying glass.
Choose your printer's PowerRIP X PPD from the list below
Click add and your printer will added to the list.
*SPECIAL Instructions for the Epson Stylus Photo R800, 1400, R1800, PRO 3800
For the following printers, Open the PowerRIP X Utility and go to "File" and down to "Add New Printer"
Only for the Epson Stylus Photo R800, 1400, R1800, PRO 3800
If you have installed the Epson driver for the Epson Stylus Photo R800, 1400, R1800, PRO 3800 and created an Epson printer you will see it on the list. Select your Epson printer and then choose;
"Add PowerRIPX Printer"
Create a name for your PowerRIPX printer, and hit OK ,and OK again.
Your printer has just been added
END of Powerrip instructions
I don't know if you did the above, but you might try deleting the old printers and adding a new one per the above.
ON OSX 10.5 upgrade:
If you upgraded, how did you do the upgrade? A lot of users had problems if they chose the simple Upgrade on the installer rather than the Archive and Install option (or a complete wipe of the drive and full install). If you did the Upgrade path, some of your problems could be caused by that.
Using OSX 10.3.9 on a G4 & G5