Some ideas:
The SQL file 010-D1215-00.db was good for figuring out some basic things (the different tables, their contents, etc.).
Its small size made it easy to handle and examine.
Unfortunately, it seems to be difficult to get reliable original coordinate data for the 'nodes' in its tables.
So, maybe, we should switch now to an area where reliable original coordinate information is readily available.
Such an area would be Europe.
Unfortunateley, the associated .db files are much larger.
I will look into the matter and report back here.