Please see the below links for the latest version.

Direct link: https://www.dropbox.com/s/uoecy8vhf724kf2/RuneSkills.js?dl=1
More information: http://mjshi.weebly.com/mv-rune-skills.html
Forum post: http://forums.rpgmakerweb.com/index.php?/topic/62070-rune-skills-skill-system/