I tried to make a custom material (for the first time) in order to simulate a blue tinted glass with low visible transmittance. It was successful in that the material showed up in my options, and allowed me to run a simulation. But it seemed to allow more light in than I had expected, so I'm wondering if I did something wrong. I compared results of a material provided with DIVA: "Glazing_70Tvis" and my new material: "Solarban_60_Solarblue+Clear" which has a much lower %tvis. I will attach an image of the same space with glazing using these two materials.
# Glazing: Tau_vis = 0.70;
# visual transmittance: 70%
# visual transmissivity: 76.3%
void glass Glazing_70Tvis
3 0.763 0.763 0.763
# Solarban_60_Solarblue+Clear: Tau_vis = 0.45; SHGC= 0.28 ; U-Value= 1.36W/m2K
# visual transmittance: 45%
# visual transmissivity: 49.07%
void glass Solarban_60_Solarblue+Clear_45_Tvis
3 0.4907 0.4907 0.4907
I'm not 100% sure if this will help - but try taking out the "+" from your custom material - it may not like this character.
I agree with Maria, the simulation may be lacking materials entirely if Radiance doesn't parse the plus correctly. After editing the material.rad file, make sure to re-assign materials to that layer.