WordPress has a cool feature. It's called child themes http://codex.wordpress.org/Child_Themes
Essentially, when people download/buy themes, they want to make certain changes to make their site unique. However, any customizations are always in the danger of being wiped out with updates. That's where child themes come in. Insead of editing the theme files, one can make create a child theme. Mostly this means creating a css file with styling that should override the theme's default styling. The customization made in this way via child themes carry over to the next versions after theme updates.
A similar concept is utilized for this vQmod, which has been created with the very simple purpose of creating the ability to customize the default theme with CSS such that such customizations carry over to the next versions after update.
You will need some knowledge of CSS http://www.w3schools.com/css/
And you'll find Firefox plugin Firebug handy https://addons.mozilla.org/en-US/firefox/addon/firebug/
Please read documentation!
Support is at http://forum.opencart.com/viewtopic.php?f=131&t=61534
I hope you enjoy this extension. If you'd like to donate, please PayPal at firstname.lastname@example.org