@Sinuce. Thanks for your question. You can easily customize the plugin by using parameters. A complete list of parameters are available on my website: http://michaelgilkes.info/joomla-plugin-easy-folder-listing-pro/
More specifically, if you want to customize the column text, you can either do it in the plugin manager, or do it specifically for each instance in your article. For example:
{easyfolderlistingpro folder=’somefolder/somewhere’|filetext=’Filnavn’|sizetext=’Størrelse’|datetext=’Dato’}
Hope this helps.