Can't get translucent material to render out to a model

[XFunc_CaRteR]

I made a model in Propper, and it has a material on it that used to be a decal, but I converted it to a normal material. During render of the model it converts the lightmapped material to a vertexlit one. However the material has the $translucent setting. In Hammer the model looks fine, but when I render the map the former decal has disappeared.

Can anyone help me with this? Thanks.