I installed it on my Slackware 15.0 system and it went great, But one warning, you may need to add this exact line to the very first like of some .el files. Then maybe “compile” the .el files to .elc

;; -- lexical-binding: nil --

I had to add it to ~/.emacs, ~/.emacs.d/elpa/elpher-3.7.0/elpher.el and file ps-ccrypt.el to avoid an error message that kept popping up.