Answers Needed: Screenwriting Labs & Colonies

A documentary filmmaker making the transition into narrative asked me to recommend labs to develop their first screenplay in. We all certainly know of Sundance, and there are the prestigious MacDowell and Yaddoo colonies, but where else can one go? And what are the rules for MacDowell & Yaddoo? Who and what is eligible? And aren't they more like a place to work and consult with other artists as opposed to the Sundance model which is in depth meetings with mentors?

The Nantucket Screenwriters Colony has helped to advance both COLD SOULS and TEETH. The Hamptons Film Festival Screenwriters Lab helped Caitlin McCarthy and others develop their work.

Where else can one go? Does anyone else have some suggestions? And what do you think of these programs anyway?