What are you changing to get it working? You should change the blend mode to Translucent and put your opacity into the opacity slot. Your colour you can put into the diffuse or emissive slot.
Well, the diffuse is generated from a vectorparameter. When I change it to translucent you get the white look you see there. I've then tried plugging the ALpha channel of the vectorparameter (value 0-1) into opacity. I have also tried using a gray texture imported from photoshop as well as using the 1 input node (cant…