Serious Play Pro community member Denise Meyerson, who is one of the Master Trainers of the LSP residing in Australia has written a great resource for Serious Play facilitators. It is the eBook Better, Best, Brilliant: The Essential Guide For Trainers and Facilitators
The book is a great resource for the use of a long list of essential techniques and more advanced facilitation techniques (including Gamestorming, Visual facilitation, use of metaphors). It also includes a prominent section on Lego Serious Play with some particular roadmaps that you can use in your facilitation practice. The roadmaps are hands on, specifying particular time segments that you can use in your client intervention assignments.