Here's an example:
As you can see, it's pretty straight-forward. I'm just using the source of the LensFlare and adjusting the properties to fit the scene. With this, I get fading up close, fading far away and other nifty transforms based on distance and screen position.
In my current project, I needed sequentially numbered labels from 1-9. I really didn't want 9 textures, 9 material instances and 9 lens flare objects in my library. If I had to update any of those things, it would be an ordeal. Admittedly, a MaterialInstance would have helped a lot, allowing me to make changes to all the labels fairly easily. However, the LensFlare system does not have an instancing system, so I'd still be stuck with 9 lens flares to adjust. Blech! I REALLY wanted to find a way to avoid that and have a single texture/material/lens flare to deal with, and I think I found a good way of doing it.