Combinatiion orifice/weir in SWMM 5.0

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I have been using Hydraflow Hydrographs for some time now and am trying to cross check output flows using SWMM 5.0 to see how great the difference would be in output. The problem I run into is trying to model a combination orifice/weir in a catch basin. I am essentially choking down flow in order for it to "back up" into a storage node. In Hydraflow, this is easily accomplished. In SWMM 5.0, I can either run the weir and orifice in succession but not in combination (one on top of the other), the point being that once the water level reaches a certain height in the catch basin that the orifice cannot control, the weir takes over and allows flow, thereby preventing flooding in my pond (storage node).

My catch basin is 5' in depth. My orifice is circular with a 1' diameter. My weir crest height is 3.5' above the invert of the catch basin (allowing a space of 1.5' to the top of the catch basin). An 18" culvert discharges my storage node into said catch basin. I also have an outlet culvert from the catch basin, sized at 18" (due to county regulations).

Any help into this matter would be greatly appreciated. Thanks.