Removing a function link at e.g. the start function of a screen, through the "no selection" button in the "function selection dialog", where the function is the function of a sub project and the sub project is not loaded, leaves a dummy link to the project while the project is loaded. When a function is removed via "no selection" in the function selection dialog, while the sub project is not loaded, the project reference should also be removed.
An issue was addressed at the zenon object links. Now, it is possible to remove a function via the "no selection" dialog, when the project where the function exists is not loaded.