ORD SUDA Elliptical Pipe Capacity

Is ORD Drainage and Utilities not able to calculate the capacity of elliptical pipes? My model is outputting a capacity of 0 for elliptical CMP and I'm not sure if this is an error or if it's impacting the hydraulic computations inside the model. The model is able to compute after two iterations. I've also noticed the program "forgetting" the pipes size, seemingly at random.