When I use PPL, the textures are black, for me it's a belding problem or a multitexturing problem.
Now, the source code is available to download so I hope that it will be more easy for you to try it.
F ==> Moving the light toward Z
V ==> Moving the light to you
D ==> Moving the light left
G ==> Moving the light right
You can download the source code here :
Here's a screenshot of my problem :