Hi Liam:
The code for the bigger examples *is* online, but it hasn't been touched since v1.0.2:
https://github.com/BuildSysUniformMetadata/GroundTruth . It may be helpful as a point of reference, but I think that having some more up-to-date and complete (and better documented!) examples of producing a Brick model from BMS labels would be more helpful to you. Maybe that can be one of the first tasks by the new working groups?
Regarding your second question, it is emerging as best practice to separate your administratively separate facilities (i.e. different customers) into different named graphs. In the py-brickschema world, this can be accomplished by having different brickschema.Graph objects for each site, but if you're working with another database like Jena or GraphDB, then you will want to put the facilities into different graphs.
Best,
Gabe