We want our community to have specific forums, galleries etc. for each market/language, but all modules seem to be global in nature. Is there a good way to have a synchronised (but translatable) forum tree for all markets, but with specific forum posts for each?
Not totally sure of what you want to do, but it seems like you could use something we call site partitioning. In the Community platform you can specify multiple "sites" - be aware this is not IIS sites, but rather a way of partitioning user data. In the admin interface you can create several sites. For almost all the methods in the community there is an overload that takes a Site, passing in NULL will be the global site, but you could also pass in a "sub site".
Maybe this could help...