It is being translated like before, by the official translators who have access to certain beta versions.
Irish isn't an official language/translation for Plus!, so you have to wait until Plus!Live is released to start the translation.
The system of translating is exactly the same as before. Plus! Live will also contain language files in the form of 1 default English INI file and several translated INI files.
The topics and keys in the translation INI file are all different for Plus!Live, not much can be ported from Plus!3 to Plus!Live concearning the translation, everything needs to be done from scratch.
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Only real official languages are included and only those languages which have a big userbase. Other translations, like dialects (locally or not, officially or not), similar languages (eg: American vs. English), made-up languages (leet-talk), etc will not be included in the official setup package. Though, this doesn't mean they can not be created. And some will even be available for download on the official site, others can be downloaded from their respective thread on this forum.
If your language is a real existing and official reconized main language, then you can send Patchou a request as stated by traxor.
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To be able to make a decent and good translation, it is very adviseable to first read:
http://www.msgplus.net/help_language.php
and:
http://files.msgplus.net/data/TranslationGuidelines.doc
The main instructions, general suggestions, etc stated on the above page and in the above document are written for Plus!3, but logically also apply for Plus!Live.
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