Hello Pilou,

an example file will not help. It's a question of the workflow. At first, it works only for solids and joined surfaces. To use, you have to use it in combination with the BrepNameSubObj node.
Start with a creation of a solid with edges you want to fillet. After that, insert the BrepNameSubObj node. Wire from the solid to the BrepNameSubObj. Node and press run. The node names the edges and faces and displays the geometry. Now select the edges like in the normal moi environment. Then insert the fillet node. It tooks the names of the selected edges and stores it. After that wire the fillet node, that it gets the geometry.




Wire the result to the output and switch of the visible in the BrepNameSubObj node.
Be careful - the fillet node can crash moi, if the factory can't find a result.

Have a nice day
Karsten