Bug fdo#63984 appears to have been raised as a result of lack of response less than 24 hours after this question was asked. Three days after that the OP asked the same question over on the AOO forums, where a solution was provided, which I am going to repeat here for simplicity:
I ran your macro that creates the Listener and then modified one of the input cell for D15 and the macro worked. I do not see any automatic running of the Listener creation when the document is opened, so I think you have to add that. […] Go to the menu Tools → Customize and then select the Events tab. Click on Open Document in the list of events and then click on the Macro button. After a few seconds a Macro Selector dialog will open. Your document should appear in the list of Libraries on the left. Click on its + sign, choose the library and then select the macro that creates the listener from the list on the right. Click Ok to close all the dialogs. Save the document and close it. The next time you open the document the listener should load automatically. (courtesy @FJCC over at the AOO forum, to whom the credit for this answer belongs)