CabinetBuilder will not build a carcass with the curved shape - just the fronts. The rationale was that the carcasses under the curved counter would be rectangular and therefore encased in a framed finished enclosure. If this is the way you see your millwork piece buillt, then configure the carcasses with the carcass objject and use the other bits to build the front(s).
Think Like a Spec Writer
AC4.55 through 27 / USA AC27-6000 USA
Rhino 8 Mac
MacOS 14.6.1