Dynamic Shadows / Lighting

[Iron_Panda]

Hey guys, I have a small diorama of a building with a number of props and I want to do a day night cycle but without the sky (so it's just the lights that change). But the problem I have is that the base of the diorama has a faded effect around the edge as it's translucent in the material editor but I know the material has to be masked which just gives pixelated edges which looks horrible.

In the scene I have a Moveable Dominant Light thats set to interpolating

Is there any way of having dynamic shadows on translucent objects?

Here is an image of the scene I'm trying to do it on:


Thanks for any help!