Here:
https://www.transifex.com/projects/p/xoops-257/language/da_DK/

You can see only one admin.php into language\renametoyourlang\
named
257[language-renametoyourlang]admin.php

The other files are outside.


[language-renametoyourlang]admin.php was for Xoops 2.5.6
and
admin.php for Xoops 2.5.5


To download from the website Transifex manually, you only have for example to click on 257[language-renametoyourlang]admin.php from here:
https://www.transifex.com/projects/p/xoops-257/language/da_DK/

Then, click to "Download for use" (for you it is in Danish).