Here's an example of the code I used to modify the colors in the shi_channel indicator. The channel color was green all the time. I modified it so that depending on if it was an up or down sloping channel, the color would either be green or red.
Take a look at the IF statement to see how I did it....
Code:
ObjectCreate("TL1",OBJ_TREND,0,T2,PP+Step*AB,T1,PP);
// Channel is Green if width is greater than ChannelAlert (Default 50),
// otherwise it is Red
if(ChannelWidth >= ChannelAlert) {ObjectSet("TL1",OBJPROP_COLOR,Lime);}
else {ObjectSet("TL1",OBJPROP_COLOR,Red); }
ObjectSet("TL1",OBJPROP_WIDTH,2);
ObjectSet("TL1",OBJPROP_STYLE,STYLE_SOLID);
All you need to do is create an IF statement, and based on the outcome of the IF statement, the OBJPROP_COLOR will be set to this or that color.
Hope that helps.
Keris