Exported to Garageband but GARAGEBAND HAS BUGS I THINK!
Thought I would post this back just in case anyone else ever finds themselves in a similar position.
There is no facility as far as I'm aware to alter your vocal track in keynote. What I mean by altering is, adding vocal warmth to your vocal narration or a little re-verb for instance. The only thing I could do was to export the presentation to Garageband. I did my timings and recorded the presentation first. My vocal track didn't get exported and I had to re-do it in Garageband. I actually preferred this in a way.
FILE>SEND TO>GARAGEBAND
This worked but it wasn't very clear in any of the instructions or help files that I found. Not very impressed about that... Maybe that was just me though, I dunno?
***One word of warning, I ran across this little error in Garageband. I simply had the presentation and a few other files stored on the desktop temporarily. I ended up moving them to the designated folder and continued on with my narration. Once I was ready to export it all to movie format, the export appeared to go through but no file was output! Tried this a few times with no success. There was NO error message!
Then I moved the files back to the desktop and it worked!
I get why it happened and I realise it was my own stupid fault but I think that's bad BAD programming. Surely it aint that difficult to write up an error message?