Thank you! I will add it in service release 2.4.2 (when it's ready, of course!)

The Kickstart translation INI files are supposed to be stored in the same directory as kickstart.php itself. Since Kickstart isn't Joomla! specific - I've used it to install Wordpress among other things - there was no point doing otherwise

The reason I don't want to include the translations with the PHP file is two fold:
a. It makes the file unnecessarily large (up to 75% bigger!)
b. The INI files have to be converted to PHP arrays. This is a major drawback concerning the administrative overhead involved (creating custom script to do that, name them properly, include them in the file build process...). Moreover, there are many users who just prefer to use English instead of their native language. I know of at least one: myself

The name of the language file is actually the easiest way for Kickstart to find them. The browser passes a list of preferred locales (e.g. en-GB, el-GR, etc) to the script, so I can test which file is present and load it in just two steps

Thank you for submitting the translation files!

Kickstart is meant to be stand-alone. It doesn't require Joomla! because, um, it is mostly used to kick-start a Joomla! site installation

If you want to select a language for Kickstart:
a. Upload kickstart.php and ONLY the INI file for the language you want to use
b. Make sure your browser is set with that language as the default to request from the web server. On Firefox it's Tools -> Options, Content tab, click the Choose... (last button) and modify the language list so that your preferred is on top.

As a bonus, if you use a localized version of your OS and a localized browser, your local language is automatically set as the default. If you upload kickstart.php and all of the INI files, your language will automagically load.