Orcad 10: print of multiple layers on the same ***

Hallo,
my question is:

Q: how do I print on a HP laser color printer (so HPGL is ok) two
layers (ie. Top and Bottom) with their respective colors (i.e. Green
and Red) overlapped on the same sheet, not on different sheets?

I wandered through Post processing options, under Preview command and
related commands; I always see one layer at a time (in blue, and if
you want you can change color), but I know I did, once! I remember
that there is a window somewhere where you force "color print", but I
can't find it.

thanks for your patience
and nice holidays fo everybody

andrea

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