Above posts are pretty heavy stuff for someone like me...

For a dummy like me... here is a set up lit and rendered as I would in P7 and the same set-up in P8 with IDL. Any advise on how to tackle figuring out a basic render like this?

In the IDL renders it look likes my surfaces are emitting light but I have 0.0 ambient and a 50% gray in the diffuse.

Is there a simple way to just "turn down" the IDL effect a few notches?

My tests are telling me I need to give up the old six and eight light sets I have been using and to work with only one to three lights but I am also getting the feeling there is some sort of interaction between RayTrace Bounce settings and Indirect Light Sample settings... I haven't worked it out :)