hey Biz welcome to the forums, if you check the community guide
http://forum.thegamecreators.com/?m=forum_view&t=131868&b=21
You should find your answer there. I do believe that you will have to edit the fpi to include the sound path of the entity that will be speaking. Youll want to save the sound file in Thegamecreators\fpscreator\files\audiobank\user.
Open the character settings, scroll to the bottom where it say soundset and below that it should say sound. That is where you'll place the path to the audio file.
I think the code would look something like this but I am still learning. you'd probably want to use the scancodekeypressed= condition to trigger the conversation.
:state=0:plrsoud=$0
:state=1,scancodekeypressed=50:plrsound=audiobank\user\yourconversationhere.wav
You should be able to have several lines of question and answer type conversations by using the scancodekeypressed.
Check out the comm guide the answer lies within.
hope it helps