Hi Gunter, for lofting and sweeping you'd do it like this:

Select these 2 and do a Loft:


Right click to finish the loft, then select these 2 and do another loft:


To do the sweep, select this as the profile curve, then run Sweep:


Then select these 2 as the rails for the sweep:


Now select the 3 surfaces that were just constructed and run Edit > Join to glue them together, then select that object and run Construct > Planar to cap off the bottom.

Also another way to do it would be to construct a full disc shape using Revolve, then build 2 slanted extrusions to use as cutting objects with boolean difference.

- Michael