Blender 2.77 - Blender Internal
Hello, I'm trying to make a simple animation about files entering an envelope. I have some troubles with "Import Images as Planes", they don't cast transparent shadows, despite I checked "Raytrace" (or Z-transparency) on them, and "Receive transparent shadows" on the envelope's material.
Envelope material settings, PNG settings, and the result:
Here's the full project:
The example is frame # 397
After days and days, I still can't understand where I go wrong. Please help...