One of the things that you may not know is that Lightroom preset files are actually fairly easy to edit outside of Lightroom. The .lrtemplate files are just plain text files formatted as XML code. So, while not for the faint-hearted or technically challenged, if you know what you’re doing, you can actually open the files in a text editor and make changes. Obviously, you don't need to use BBEdit for this, any high-quality text editor will work.