- There is an advance functionality which gives you access to all the design/calculation parameters. It requires some little text manipulation but I am pretty sure you can find a solution of your problem in this way. I do attach the .fdscript documentation as it is pretty much equivalent for C#
FdScript | FEM-Design API
The method that you need to use is called SetConfig and it is part of femdesignconnection class.
Let me know who it goes 