Still trying..
Properties should be set (more or less) correctly now, but there is
still the problem with node border width which is not always kept
correct whenever I change the activity ratio (SHOWN_LEVEL) on a node or
edge. Even re-applying the visual style and updating the network view
does not seem to always work. However, the "Clear all edge bends"
right-click command on the network (Networks panel in the Control Panel)
seems to make it right: what do they use there?