NASA has done some studies in checklist design. In particular, you might find the publications from Asaf Degani interesting.
Here is a quick search result for Degani + checklist.
CAP 676, "Guidance on the Design, Presentation and Use of Emergency and Abnormal Checklists" may also be useful; I don't know if this deals with colour, though.
Finally I know that Boeing is currently studying a complete redesign of their QRH procedures, including a new colour lay-out for emergency checklists; perhaps they could provide you with some more information too.