Is there a way to simplify these lines. For some reason these nodes are giving null values and not completing.
I’m not familiar with how those nodes work, but have you checked to see which curves are returning nulls? Do you have gaps or missing curves in the final output? Is it possible that those curves are being removed or combined with other curves in the simplification process? The fact that both custom nodes are returning nulls without warnings makes me think it’s an expected outcome.
Also, just to be safe, what does the warning on the polycurve say?