http://perl-win32-gui.sourceforge.net/cgi-bin/docs.cgi?doc=userguide-concepts, subhead "COLOR"

See also http://perl-win32-gui.sourceforge.net/cgi-bin/wiki.cgi?Change_Listview_Item_Color.

Also of possible interest:

Textfield does not support EM_SETBKGNDCOLOR. have you tried this:

    # change to red
    $Textfield->Change( -background => [ 255, 0, 0 ] );
    # repaint the control
    $Textfield->InvalidateRect(1);
[download]

(found at http://www.mail-archive.com/perl-win32-gui@httptech.com/msg01720.html)

The search box on the Win32:GUI site at SourceForge turned up numerous other references to; questions about; and answers. You may profit by directing your research (pun intended) there.

Uupdated with additional references