Firstly, this is constructed in Civil3d Parts builder. You may not get many responses due to suggesting it's modelled in IPE, not many of us use that package.
Looking at the Xml, I can't see a rim to sump height (RSR). The drainage features work best when they know the level of the base so they can be drawn correctly. This would either be the surface level or an overridden cover level.
The RSR value is calculated from the Rim Elevation and Pipe invert Elevation so the structure is defined from the invert level as calculated.
I usually use a cylinder (0.001 Dia) which is created from Top (where autolayout data is located) to the RSR depth to design this with the workplane designed from this offset, the solid which is created can be hidden and will never appear but will be visible to the program in analysis like intersections. All other geometry is defined as offset from this. Alternatively you can offset to the top of the object and work down, the approach depends on what you are creating.
Mike
Mike Evans
Civil3D 2022 English
Windows 7 Professional 64-bit
Intel(R) Core(TM) i7-3820 CPU @ 3.60GHz (8 CPUs), ~4.0GHz With 32768MB RAM, AMD FirePro V4900, Dedicated Memory: 984 MB, Shared Memory: 814 MB