Civil Cell for Curb Ramp

I want to design a curb ramp (CR-A) in 3D ORD but don't have the 3D Civil Cell. So when I put the 2D Curb Ramp it doesn't let me to clip the corridor. Does anyone know how would I get the 3D civil cell...
ORD DU - Curb Opening Inlets - Length Required

While I know Efficiency is the ratio of Actual Lenght to Required Lenght - is there a way to annotate or label the length required to capture 100% of the flow in ORD DU?