Circular to rectangular adapter for HVAC duct

In case someone else is in need of a similar model, I am sharing this design for a transition between a Circular and Rectangular ventilation duct.
The current model is suitable for an ø125mm "Spiro channel" with gaskets, and with the dimensions and offset that I needed for my use. You need to tweak the parameters in the spreadsheet in the FreeCAD file for your application. You also need to revisit the circular sketch while you keep the rectangular profile visible. The reason is that you need to adjust the split between the arcs that make up the circles. I tried doing this with circles first, realizing that my 3D print would fail every time at the same layer, due to an inconsistent loft section. The loft function will try to adapt the two sections/sketches so that they have the same number of segments, and you simply need to help it. Have a look, also see the attached sketch, and you will know what I mean.
I printed this with nylon (PA), which is a really tough material. In case your 3