I am using camera tracking to make a short film and in render viewport you can see what I am trying to add (yes, those are butterflies).
After rendering the scene the butterflies appeared transparent
As you can see in the first image my material is very basic on the butterfly.
Here are my compositing nodes:
They are the default camera tracking nodes... in blender internal.
I am using blender v2.77 on windows 10 with the cycles render engine.
A similar, yet, unanswered question: Why won't objects appear in motion tracking?