I have no problem about receiving Tweets, but I am not able to send any tweets.
However, it works without any problem if I use/install "twitter-for-geoevent" (2014/1/31 version?) from GitHub at: https://github.com/Esri/twitter-for-geoevent I can send tweets with this file.
Is there any difference between those two, Gallery one and Github one? If so, will gallery one be updated soon?