I have a model loaded into Invigorator and I have "use comp camera" and "use comp lights" ticked as I want to use AE's cameras and lights. So that my model can cast a shadow I've set up a shadow catcher plane and this is working perfectly. If I throw a spotlight onto my model it casts a shadow as expected. However, no matter what intensity I turn my lights up to, it makes absolutely no difference to the brightness off the model. If I point a spotlight directly at the model and turn the brightness down to 50%, it looks exactly the same even when I turn the light intensity right up to 1000%. The only thing that the light intensity seems to change is the darkness and lightness of the shadows (mediam at %50 brightness, jet black at %1000). The model itself remains exactly the same intensity. Just to make sure my lights were working correctly, I placed an AE solid directly in between the model and the light and the solid reacts as expected to the light.
Just a small update: I notice that even when using the Invigorator lights, it seems impossible to overlight an object. As an example, if I go into the Invigorator lighting control panel and point an Invigorator light at part of my model and push the intensity value to 100% I'm getting the effect that I expect. But there are occasions where I want to have even more light on a particular spot, and I can't seem to be able to do that. I've tried positioning other Invigorator lights pointing at the same spot, all with 100% intensity, but the brightness of the model is unaffected. Whether I point 5 lights at 100% intensity, or one light at 100% intensity, it makes no difference. I assume the only workaround if I want to have a model REALLY bright up would be to add an AE brightness/contrast filter to the Invigorator layer?
Try adding a Reflectivity Map. When you add a Reflectivity Map to an object, this makes the object reflective and will react intensive to lighting. With the right angle and lighting, it will really light up your object and may turn the object white from the lighting.
This should get the effect that you want on the object. Hope this helps.