Hi @fmaillet, sorry for the inconvenience, you will have to add the DLL into the Lib directory of the visual studio project.
For an explicit introduction you can follow the building tutorial @ https://tobiitech.github.io/interaction-library-docs/wpf/html/gettingstarted.html
which shows how to build the samples included in the interaction library ZIP file. Please go through this and let us know how you get on. Best Wishes.