For details please see and cite, if you use, the following publication
https://doi.org/10.1016/j.softx.2020.100495
Ayala, H. V. H., Gritti, M. and Coelho, L. S. An R library for nonlinear black-box system identification. SoftwareX, 2020 (to appear).
A list of desired features can be found in the paper. They are all pending :)