I encourage you to check out my other themes on ThemeForest. Here is a link to my portfolio page: [http://themeforest.net/user/pxThemes/portfolio](http://themeforest.net/user/pxThemes/portfolio?ref=pxThemes) or check pxThemes website here: [pxt.be](http://pxt.be)
You can use Grunt and Node Sass. Just cd into theme folder and run ````npm install```` (with 'sudo' if you're on Ubuntu like linux) and then ````grunt```` to compile scss file and also 'watch for changes'.
You can see Gruntfile.js for configuration changes. You can also play with other Grunt tasks here.
Of course if you want you can still use Ruby version. Just go to assets folder and run ````scss --watch scss:css````
But I think that Libsass/Node version is much faster.