ENBSeries v0.126, the latest version, is suppose to be the more optimized than previous versions, but I have a huge FPS drop when using it. Why is this?

Also, where's the GUI for editing the settings?

http://www.enbdev.com/mod_tesskyrim_v0126.htm

"This version contain many quality and performance optimizations from previous four, including optimization of reflections, plus GUI for editing enbseries.ini config."