Having spent a few hours getting familiar with FreeCAD, we decided to create something actually useful: some exploded diagrams of how to construct our 28mm wild west buildings. Having taken out the mistakes we found during assembly, we just need to finalise the designs - add in a few more tabs, to make construction just that little bit more intuitive - and we can create 3D models of all our buildings.
Starting with the simplest (and before we added in extra locating tabs, d'oh) we managed to put together a reasonable 3D model of our "bank" building
A few components got accidentally deleted, as we battled with ungrouping "compound parts" (simply delete the overarching compound and the component parts become individual again) but the end result was quite impressive, for our first real venture into creating 3D models (rather than just re-positioning models created by someone else).
So now we just need to decide where to add in the extra locating tabs, and we're ready to produce some step-by-step assembly guides - complete with 3D exploded diagrams!