Hello, not a question, but a tip.
As explain somewhere else, copy the English language files to another language_country directory e.g. nl_NL. As a result you will find the Dutch language as an option in the standard adminstrator panels for language support. Of course the files still contain English phrases. You can override the files with available language files for components/plugins.
Still sometimes you need or want to edit the language files yourself.
Now get the Translation Manager extension and you get a nice overview of every language file, you can use the good GUI to edit each phrase to you liking (with the option for resetting). Keep track of your updates.
Hope you like it as I do, Bart