- You have to cycle. Is it really that common to switch between different styles between multiple copy operations? In my setting, I work for hours with the same style.
- The best would be that you make it available at https://github.com/citation-style-language/styles. If your style is too specific, put it in the root of the JAR file. Just open it with 7zip.
In case CSL is too complicated, JabRef offers its own language. See http://help.jabref.org/en/CustomExports for the full language reference. The content of that preview can also be copied.