Can anyone help ?  Someone suggested that I use Modelica for modelling a complex dynamic mechanical system : I have experience of another graphics-based dynamic modelling tool, but I no longer have access to that and need an open-source tool.  I've opened the Open Modelica Connection Editor, it appears to be able to give me the functionality I'm looking for, so I'm trying to work through the Tutorial's first example (the simple pendulum).  I've found and pasted the icons onto the work space, but I can find no way of connecting them together ... I've clicked on the 'Connect/Unconnect Mode' button, but it seems to have no effect.  I can draw lines, but they don't connet to the components.  How do I connect the model elements together ?  I've been defeated at this very basic first step.

More generally, I need a tool that is GUI-based only, I am not prepared (or probably able) to learn the code that almost all the documentation seems to be full of.  Is this the right tool for me ?