I think the front page of the GSBPM case study template would be useful also for GSIM.

I suggest replacing metadata by information modelling

Is the number of sites an interesting/relevant question?

We will need a Lessons Learned page and an Attachments and Links/References page.

Unfortunately the contents of "2 Modelling the Information and Processes of a Statistical Organization" in the GSBPM Case Study will/should overlap with the GSIM Implementation Case Study. Maybe we can move (2.1 Statistical information model and 2.2 Adoption of GSIM) and/or copy (2.4 Relation to other models) content giving people a flying start? Or maybe we don't need 2.,1 because we are only interested in GSIM and 2.4 is redundant since the documentation of GSIM provides the Relation to other models?

Maybe we need a section/page for Principles and we could have subsections for Design, Decision etc?

Any implementation will have Extensions to the GSIM and should have a description of (intended) Users/stakeholders.

There should be a System overview then a description of modules/components.

There should be a Process description then a description of subprocesses that are supported by the implementation.

Should we have a section for Licensing?

Obviously I'm hoping for Creative Commons for Design documents, but if we get any software components in time, then should they be stored here or should they go into the Global Artefact Catalogue or an appropriate software repository ...? 

Wowsers Jenny.  You're on fire!  It's home time but I will look at all your comments tomorrow and make an outline template for others to be inspired by.  Thanks so much for getting things started!