Change family type and save image repeatedly

Hi,

I watched the discussion and followed the setting from the link below, but I can’t have any image saved to the directory I navigated to it. I tested the two steps individually, and pretty sure I can make the family change types one by one, and I can save a bunch of images one by one. But once I compose them together by the “function.compose” node, I can only see the family types change one by one, no any image changed. Can someone help me here?

http://dynamobim.com/forums/topic/changing-family-instance-and-saving-image-issues/