Hello
I have double checked that, ive done multi lang sites many times, using k2, and this is the first time i see this, thats why i post this on the forum, im not newbie in Joomla.
I have that module and everything is in order (as i said, ive done this many times).
If i filter by language the page just reloads and i have to go to the database and change the Language of the item to "all" in order to see it again. I will try reinstalling k2 and see if it fixes it.