Why does my SBML model contain no species or reactions after a convertion from CellML?
The issue is that there is no annotation in the CellML file that could help the converter to determine if a certain variable is a SBML species, parameter or compartment. And the same apply to any CellML equation. The current version of the converter is not trying to do any complicated guesses and therefore converts every CellML variable into a SBML parameter and all the equations into rules. We are currently trying to define some annotations that would allow to create better SBML files from CellML and vice-versa, the ultimate goal would be to be able to do a round-trip conversion, starting either from a SBML model or a CellML model, without loosing any informations.