Need help with custom shader and receive shadow

Hi everyone,

It's been a while since I needed help, I guess I'm getting better but I'm facing an issue I just can't fix. I find shader language to be very hard to read and understand. I managed to mix an outline shader with the ATS Snow Suite snow bumped shader. So now I have dynamic snow on my buildings and if I select them I can toggle an outline around them.

The issue I have is that the shader does not receive shadow. the object casts shadows and it looks great but if there's a tree nearby the shadow of the tree just cuts on the ground and does not appear on my building. I looked online for possible solutions, changing the fallback, using other pragma directives, nothing works. It either doesn't change anything or turns everything to pink.

Can anyone take a look at my shader code and tell me if it's possible and what to add in order to receive shadows? http://pastebin.com/PfKCGvZR

Bonus Question When I select a building I call a function on it that does:

Code (csharp):

1. highlight.a = 1f;
2. MeshRenderer.material.SetColor("_OutlineColor", highLight);

Doing this creates a new instance of the material which is fine. When I deselect, is there any way I can revert the material to the original and keep batching intact instead of keeping an (instance) of the same material?

Let me know if it's not clear.

Thank you!