What is MPRMCNS?

Hello, I am a new Modeller user and I've managed to read my sequence alignment in and CHECK it using the model-default.top script, Modeller even writes out a .ini initial model, but then stops saying:

mkspline_E> too many parameters, increase MPRMCNS

Please could you tell me how to do this, or how I can get round this problem? Thank you, Susan Crennell