http://www.graphtecusa.com/products.php?cat_id=1&visit=img&series_id=38&view=D&driver=79
That is the Windows driver for that printer.
That should be all you need + Corel X4.
OH - except for the fact that it leads to 'page not found' ;)
You could email them and make a request for the file.
OR just use HPGL in the Corel export menu
There is this that you can use to send the file to the printer
http://pages.cs.wisc.edu/~ghost/redmon/
Maybe something else too I'll have a look.