Thank you for the help.
I have tried the solution you provided and it does not work (concering the addition of the word Hello for instance).
Moreover, I also think that there is a conceptual mistake in the script that I posted (to which yours is a slight variation):
I select an object in order to add the ring, say a cell, and the bbox that is in the code refers in the bbox of the cell.
The word that would be added in the ring should be not related to that object, but to the ring itself
(thats why I initially stated that the location of the word in the ring should be relative to e.g. metal6 of the ring).
But as I said before, even if the problem of the location of the word would be ignored, I did not manage to see any solution of adding the text by using the lines you provided as they are (only by simply substituting word-->Hello).