Konstru supports Floors as purely horizontal elements and walls as vertical elements. This means, if your floor is sloped in Revit, it will arrive horizontal in Konstru. This is due to a limitation of the Revit API, but we are currently working on a solution to improve this and support slab shape point edited elements. We won't be able to create sloped walls in Revit at the moment and the near future.
Currently Konstru is setup in a way so it identifies areas from ETABS and SAP as walls if they are within a small tolerance of being fully vertical, and the same for floors if they are horizontal. Every element in between will be identified as an area element. Those areas are not supported in all platforms.
Similar for Columns, Braces and Beams. From ETABS and SAP Konstru identifies almost vertical elements as columns and horizontal ones as beams, while all in between will become braces. In Revit this is handled by type, if the element is a column it will remain one. Same for braces and beams.