2 headed signals - how do they work?

I have placed 2 headed signals where the junction go to 2 tracks. I assumed the top head was for straight through and the lower head is for the diverging track. Regardless of how I throw the switches only the top head changes aspect. Am I doing something wrong? I am using the BNSF signals from HP_Trainz off the DLS.

Hello there is a setting you set up on this signals you click on the signal and shows you how to set them up.

Thank you train20, that helped and easy enough to figure out. Now they are working as should.