In the main FH folder there are two files called 'Emotes' and 'EmoteHotkeys' you open these up with Notepad.
One will have a long list of Emotes and the other will have some numbers that looks like this:
0=0
1=1
2=2
and so on.
The right column equals the key on the keyboard and the left side equals the emote that will be displayed in game.
SO THEN you take a look in the 'EmotesHotkey' folder you have to physically count the names of the emotes in order to get the number to put in the left column of numbers.
For example [Normal] would equal to '0' and then [Smile] would equal to '1'
So all you have to do is change whatever number you want in the left column to whatever emote you want to have.
I hope that makes sense XD