Thank you for your quick reply.
And yeah I noticed your suggestion in one of the above links too.
The observer solution seems a little kludgey to me, especially when you can create the needed leader manually with the Text tool.
So I'm still pretty new to SketchUp development, how that observers solution would work when say I would like to move my *.skp file to the other PC? I would obviously have to move it with the script which sets up observers?