If someone creates a language that does not exist in the current list, will it not be available to all ning users (networks), or will it only be available to that specific network? So if someone translates to Swahili then I would be able to pick that from the list as well?
I would bet the answer is no. This is because we can all modify our language in the language editor. Somebody would have to translate the language into Swahili and Ning would have to upload it to make it available to all.
Great question! Tyler's right that the answer here is "no," BUT...if the NC who created a Swahili translation shared it here on Creators (as a text file), then you'd be able to import it into your network! This would save you the trouble of translating 80+ pages of strings into Swahili. I know that some NCs have shared their Danish translations here on Creators in the past.
That's not totaly true. Since March 2012 (see, for example, ticket 00597945) translation import/export doesn't functionning properly :-(