NullPointer after Reimport Model

Hi,

I have reimpoert a model to add a new output-parameter. So I made a reimport. Than a DC-Build and than I edit my model binding to add the new parameter in my context.

But now I get a Nullpointer-Exception. It seems, that it makes the model-execute and the node-invalidate but there is no data in the fields.

Have I forgot something during the reimport process?