Hello Barry,

You can have a look on this file: ../administrator/components/com_easysocial/includes/bbcode/adapters/decoda/library/config/emoticons.json. To add additional smiley, you can add another line:

     ...

	"sleep": [":z", "(sleepy)"],

	"nerd":		["(nerd)" ],

        "newsmiley":		["+_+" ] // this is a sample to add additional smiley.

Once you have added the code, you need to upload the smiley image in this folder ../media/com_easysocial/images/icons/emoji/. The file name has to be the same as stated in the file. In this case, it is 'newsmiley'. Therefore the file name is newsmiley.png. Hope this helps.