Thanks but I had already worked out the mapping. As I mentioned, I have it running in another Twitter plug-in successfully, so there is something not working correctly in this one. However, I did generate new access tokens using apps.twitter.com, but same thing happens.
Take a look at https://www.smartgradfinance.com on the right-hand side. The first twitter plug-in is yours, the second is one included as part of the design temple, Pego – Twitter Widget.