Using Yamaha P105 internal speakers.

Hi Guys, I'm a complete duffer when it comes to these things, but I'm intrigued with Virtual Piano and wanted to try out Pianoteq using our Yamaha P-105 DP. Basically, for starters I wanted to use the existing speakers in the piano, although I appreciate separate quality speakers would sound better, but just for trying out Pianoteq? So, I have the P-150 and a year old Toshiba Satellite L7500 and I'm not sure where I go from there. I'm OK with downloading the software but as I said I'm a duffer here, so any advice or pointers to web tutorials would be welcome. Thanks in advance.