Want artistic color control over shadows and indirect lighting?

Hello,
I am trying to setup a way for materials to have their own shadow tint/color that uses nearby lighting to determine the shadow tint. Someone else on the team had this working in UE3/UDK using the custom lighting pin but it looks like that the class structure for that has changed due to the use of deferred rendering. I was wondering what the best practice to set up custom shadow color control at a material level.

Also not sure if its best to try to implement this in blueprint or C++. I’m more familiar with C++ but can use either.

Look forward to hearing from you.