Just playing about with Bsurfaces, and really liking it so far, but I’ve run into a weird problem with re-ordering faces.
I’ve followed the instructions as far as I can see - I make a grease pencil stroke in edit mode in the order that I want the splines re-ordered, but when I click reorder splines I get the following error:
I might be wrong, but I got the impression that BSurfaces was more or less abandoned by its creator. Since it isn’t actively maintained any more, all kinds of issues with new versions of Blender are to be expected. The bugtracker already lists a few bugs concerning “Reorder Splines”, so I guess you encountered one of them.
Sorry, I guess that’s not what you wanted to hear…