Hi Roberto,
Although it probably should have been put in the "issues" list, a relevant comment was made by yettyn on the documentation page at the link below.
http://drupal.org/node/114760#comment-267147

I feel that the issue that he mentions is minor in the overall scheme of things, but might be considered when you do a revision. The documentation I wrote says "Choose create translation for another language. This will bring up the same content, but with the locale changed to the new language." which is not really what happens in the current dev version of Localizer. The language setting follows the current users UI language. (If I remember correctly in an older version of Localizer the entire UI would change when you clicked on the translation.)

The language following the current users UI language has been a GREAT help to me when NEW content is being posted. (Otherwise people would forget to change the language and everything would default to ANY.) However, for a translation, I can see that it would be helpful if the language setting would follow the language clicked for translation rather than the UI. Going even further, the book content has localized outline content that would be helpful to be brought over at the same time. I put my opinion at the link shown below.
http://drupal.org/node/172067

I don't know if it would be hard to keep the UI the same but change the language setting and field (like book outline) over from the new language. If possible it would be a "nice to have" feature of Localizer.