Transient magnetics simulation error

Hello,

I am doing a core inductance model in flux (model attached). In this model I have simulate some harmonics in the electrical circuit and I have some problems to make the simulation works there. How should I make the circuit and the current source value definition? Is the first time I am doing a transient magnetics simulation so I dont know very well how to set up an appropiate solving scenario. I will upload the model if you want to take a look. I would be very grateful.

Thank you,

Iñigo Izaguirre