Trial for Silver Efex Pro 2

[GeorgieGirl]

I had an old jpeg that I had messed around with in LR for B&W for fun and I wanted to see the improvements with Silver Efex Pro 2 so I downloaded the trial. I like the program's efex but the sliders are not smooth (sigh). That's not my gripe. Here is the first go round with the trial to see what it does for B&W conversion. Look at what happened to the skyline behind the splashes above the horizon. I worked on these splashes with the control points but within the circle. Its like a bad HDR at that area with the dark halo. What is this caused by and what can be done to avoid it?