I am an intern at Spark Calibration Services.They have developed a local language on geany and I am trying to add code folding points on it. I come accross this linkhttp://wiki.geany.org/howtos/adding_fold_points) but couln't get a clue. First of all, i am trying to figure out how to do this on a familiar language(ie. fortran), then i will convert this procedure to the local language. I have downloaded fortran lexer(http://sourceforge.net/p/scintilla/code/ci/c8042eb1bd3e5596d96621a5cf23958d72a4d83a/tree/lexers/LexFortran.cxx). Which directory should i add this lexer? And what should i do next?

ps: I study electrical engineering and unfortunately i don't know much about text editors. So please write the basic steps to do it.