I saw this problem when I was translating an article. And then I refreshed the webpage, but it still could not save my translation.
And I saw two same templates in my translation, but there was only one in original.
Topic on Talk:Content translation
In the English Wikipedia the CXT is temporary restricted and only permitted for users with least 500 contributions and a minimum of 30 days since signup. As Your account has no other contributions, I recommend other contributions first.
The CXT allows to select, add and fill more fields from the destination template. From the philosophy of the CXT, this should be the way to bring the data into the destination article. The other way is to fix it later when published.
Templates are not identical and most likely not compatible to other language project. The CXT allows to choose and fill other fields to make fill the translated template as good as possible. For example, the German templates are known to combine data and request unnecessary or redundant data. The English match the need of information much better.
As the templates are customized on each project, individual and discussed solutions are made of missing knowledge, not accessible information, or the try on simplifying information due a point of view on notability, fields of the template in an other language often do not match.
I decided to copy and fill the templates manually after publication. One day, the Infobox templates will be stored on Wikidata. For this reason, any intelligence in the CXT – if there is one – has no need to learn how to fit and transfer the information into the destination template.
Horizon Sunset, what do you mean when you say that you couldn't "save" the translation? Did you press the "Publish" button? Which message did you see?
I did not translate the whole article so I did not publish my translation.
I mean my draft could not be saved automatically.
However, this problem was solved.
I copied my translation and deleted it, and then I opened a new page and pasted my translation on it.
Do not forget to import the revision history to meet the creative commons licens requirements.