GPU Rendering with LuxRender - Where is SLG Path OpenCL option? Where is the option for SLG Path OpenCL?

I'm finding the online reference for Luxrender/Blender to be a little cryptic and disorganized. 

To ensure I am using GPU, I found directions that included this graphic:

 

Yet having set up luxrender, I don't get the SLG Path OpenCL option, but rather these: 



I'm guessing the problem is me, since this is my first attempt with luxrender. How do I know if I am using GPU? Is it now dictated strictly in my blender settings? 



Side note: All this trouble - perhaps I should just use cycles?
SLG has been merged into LuxRender under the name "LuxCore".
It now supports almost every feature of "Classic Lux" and contains many improvements, most notably in the speed department.

So what you will want to use is either "LuxCore Path OpenCL" in your screenshot above, or switch LuxBlend into native LuxCore mode: http://www.luxrender.net/wiki/LuxBlend25_LuxCore

To use GPU rendering in LuxCore mode, go to the render settings panel and switch from CPU to OpenCL:



Note that OpenCL rendering is only available when using the Path or Biased Path engine.