Maybe someone find it useful.
Whenever you import FBX models/objects to Blender, the diffuse intensity always reset to 0.8 or 80 by iClone units.
Blender does not preserve most other material attributes settings (like opacity maps), but I found "bleached" diffuse is the most annoying.
If you do multiple in/outs while testing, you can set the diffuse intensity manually to 1.0 for each material in Blender project, but I found very simple way to reset it with one shot before exporting a model out of Blender
Select a Text Editor
Click New
Paste following script into window and click Run Script:
import bpy
for m in bpy.data.materials:
m.diffuse_intensity = 1.0
All materials diffuse intensity would be reset to 1.0