So basically I'm just faking a color gradient that gradients over a tiny window.  So for only two colors you only need 4 points. 0, some number very close to 0, some number very close to 1, and 1.  If you wanted more than 2 colors you'd have to calculate values from 0 to 1 at each point in your range you wanted.  for instance if you wanted 110, it you'd have to add two values at 10/35 and 10/35+.0000001
 
Names Default to Here(1);
dt = Open("$SAMPLE_DATA\Big Class.jmp");
Column(dt, "weight") << Set Property(
	"Color Gradient" ,
		{{"Something", 16387, 
		{{255, 0, 0}, {0, 255, 0}, {0, 255,	0}, {255, 0, 0}}, //list of colors
		{0, .00000001, .9999999, 1}}, //corresponding locations from 0 to 1 
		Range( {100, 135, 117.5} ) //minimum, maximum and center.  0, 1, and .5 is another way to look at it
			
		}
);
Column(dt, "weight") << Color Cell By Value(1);