Hello. Thank you, for such a quick response. This of course works. Perhaps it would be nice if a warning was given when a property matches by name but not by type (?). The current behaviour is to ignore the mismatches.
Similarly, I wonder if it would be possible to simply attempt to copy the custom properties across to the new docment and warn on colissions.
The use case is as follows: I have a small number of networks, each with a set of properties. Some of those may be shared across networks. It is perfectly sensible to copy them all in one document and fill in the gaps manually to run a test. But if you first have to find the set of properties across all networks, define them as custom-properties and then copy each network across, it becomes much more practical to write the whole thing as a script. Maybe yEd could offer this shortcut.