The VGA input on the DL.2 bypasses the internal graphics engine and goes directly to the projector. Therefore, the Collage Generator cannot be used with the VGA input. The S-video input goes through the graphics engine and can be collage, however it will be much lower resolution.
The iris is a mechanical dimmer of sorts, but is intended more for the ability to do a complete blackout with the fixture (block out video black). You cannot achieve smooth fade to black using the iris.
Hope this helps. Please let me know if you have any more questions.
