From what I understand, it's all about whether that language is represented in every possible text file. If you've done a Polish language conversion under french tags, I'd invite you to offer your ability to translate to polish for the entire mod. It would be easily enough done to add <Polish>blah blah blah</Polish> to all text info files. It may require that you also mod the original civ text documents and have us start including them in our text files if you're adding a new language tag entirely. But I think for anyone who knows another language, translation projects are currently a job left largely unaddressed and should be pretty easy from a modding perspective (though it would be quite a task from a volume of work perspective!) Keeping up with changes from English only modders could be a bit of a challenge as well. Nevertheless, I don't think any of us would want to deter someone from helping us in this manner.