I tried a simple example with JMP 15 and Windows 10 and didn't have this problem. Click the red triangle and select Save Script > To Script Window. You'll see where JSL is setting the colors. You can alter the code and use your colors. Here's a simple example where I set one color to RGB of 225, 79, 113:
dt = New Table( "Pie Color", Add Rows( 14 ),
New Column( "Column 1", Character, "Nominal",
Set Values( {"aaa", "aaa", "aaa", "bbb", "bbb", "bbb", "bbb", "ccc", "ccc", "ccc",
"ccc", "ccc", "ccc", "ccc"}
)
)
);
dt << Graph Builder(
Size( 490, 435 ),
Show Control Panel( 0 ),
Variables( X( :Column 1 ) ),
Elements( Pie( X, Legend( 5 ) ) ),
SendToReport(
Dispatch( {}, "400", ScaleBox,
{Legend Model( 5,
Properties( 0, {Fill Color( -14765937 )}, Item ID( "aaa", 1 ) )
)}
)
)
);
The saved JSL shows a fill color of -14765937. If you convert this to RGB you get (.8823, .3098, .4431), which is (225, 79, 113). You can set the color with RGB values like this:
Properties( 0, {Fill Color( {225, 79, 113} )}, Item ID( "aaa", 1 ) )