Large gradient background at fault

Has anyone else had problems with printing when a large gradient colored
background exists?
That appears to be the faulty item that I've isolated.
The drawing of some 1.5Mb has thousands of text entities and behind this
text was the background, colored gradually from a red to a light green. The
drawing also has large header text, some of which was not printing.
The printer, HP 5500 60" roll, reported an error on LPT1: but not saying
what it was.
I then proceeded to subtract suspicious items from the drawing to see what
may be to blame. Finally, when I left off the solid hatch (the gradient
background), all purred like a kitten. Even all the large header text
printed as drawn.

I'm using a P4 3Ghz with 1.5Gb ram and loads of disk space under Win2k.
I'd already bumped my swap space up to it's max of 4Gb.

Any tips to allow me to place that background back in the drawing and make
it plot?

Len Miller