Update a Custom Application

We have an app that was written by a programmer that is no longer available to us.  It is late 1990's vintage.  The application used obsolete hardware and software, but it is so important to us that we would like to upgrade it.

In essence, the program takes PS output generated by the very earliest generic printer driver and processes the file to an intermediate postscript file; then a pdf file;  to produce a layout and distortion for flexo printing plates.  The app runs on a Windows NT 4 Workstation computer.  The postscript file is generated by printing a Coreldraw version 8 file running on the host machine.

I would like to create this file by running it on a modern computer with Windows 7-64 bit with Coreldraw X7 (no longer supports saving to Corel 8).  I want to eventually do away with the NT box and all non-current software.

I am stuck trying to find different drivers than might create a compatible postscript file that the custom application can use.  Any thoughts out there?  Might be a nice gig for the right person that can take this project and run with it. 
The final deliverable that the application produces is a PDF file that is used to make a flexo printing plate.