keyshot 4.1 Add/Set highlight doesn't do anything?? what's it for?

[Konginchains]

I've always been curious about the two extra settings in 4.1, add highlight and set highlight, i thought it be a way to simply set a light that only cast specularity on my model instead of diffuse. But when i use it, it has no difference from "add pin" at all. "Set highlight" on the other hand, instructs me to ctrl+click on the main viewing window to add light sources, but when i do nothing happens.

Anyone care to explain what these 2 options are for in the HDR editor?

Thanks. 

[Chad Holton]

If you want to add a hightlight (or to tone down lighting) to a particular area of an object, you would use ctrl+click and pick the area to add it in.  The editor will position the pin in the correct location on the HDR automatically.