Using multiple contours...

mcont(contour_level_selection_type = "interval",
	contour_line_colour = "red",
	contour_line_thickness = 2,
	contour_label_height = 0.30,
	contour_highlight = "off",
	contour_label = "on",
	contour_min_level = 2.00,
	legend = "off",
	contour_interval = 5.00)

mcont(contour_level_selection_type = "interval",
	contour_line_colour = "blue",
	contour_line_thickness = 2,
	contour_label_height = 0.40,
	contour_highlight = "off",
	contour_label = "on",
	contour_min_level = -1000.00,
	contour_max_level = -2.00,
	legend = "off",
	contour_interval = 5.00)

mcont(contour_level_selection_type = "level_list",
	contour_level_list = [0.00],
	contour_line_colour = "black",
	contour_line_thickness = 4,
	contour_highlight = "off",
	contour_label = "off",
	contour_min_level = -1.00,
	contour_max_level = 1.00,
	legend = "off")



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