I just translated a bunch of strings with vim, I'll post the file tomorrow (sorry, now going to bed :-) ). Later I should join transifex?

yes, transifex
translations will be sended to Djangobb Locale public repo (http://hg.djangobb.org/djangobb_locale/) from transifex

I can't see how to create an empty translation file, I was editing the french version, but I don't want to upload it as is, as it contains plenty of French strings.

http://www.transifex.net/projects/p/djangobb/c/tip/
add new translation
on u don't saw this button?

I saw it, it does not automatically create a file, one must be uploaded, but I don't have a base file or a proper .po editor at hand to clear an existing one.

ok

slav0nic@slpc:/tmp$ hg clone http://hg.djangobb.org/djangobb
destination directory: djangobb
requesting all changes
adding changesets
adding manifests
adding file changes
added 257 changesets with 1613 changes to 916 files
updating to branch default
347 files updated, 0 files merged, 0 files removed, 0 files unresolved
slav0nic@slpc:/tmp$ cd djangobb/djangobb/djangobb_forum/
slav0nic@slpc:/tmp/djangobb/djangobb/djangobb_forum$ django-admin makemessages -l es
processing language es
slav0nic@slpc:/tmp/djangobb/djangobb/djangobb_forum$ ls locale/
es/    fr/    lt/    ru/    zh_CN/ 

and uploading es/LC_MESSAGES/django.po to transifex

I translated a good amount, enough for basic use of the forum, I think, but many texts are lacking context and can't be properly translated without it, so they will have to wait.

Well, I took another look and added a few more translations, mostly fuzzy ones, so it's close to 100% (just two missing strings) with fuzzy strings.

I don't know what method is being used to translate, but usually it is possible to add "context strings", which don't show up but are used to give a translator a hint of the meaning. For example, I have no idea what "zap" is on djangobb, and "report" is a very ambiguous word (does it generate a report, or does it report someone?). What is the meaning of 'hash' as used in djangobb? Is it the technical term? "There are new messages (%(new_msg)s)" should tell what "new_msg" stands for, and what are all the (%()s) for? "For post in topic", I don't understand what this phrase means. "Moderator control" is this to change who is a moderator, etc?

Thanks!