How do I Change the subnav slug?
Very good question sir. You can define the custom slug in bp-custom.php. here is an example on how to do it
define("BPDMP_SLUG","what-ever-slug-you-want");//please change what-ever-slug-you-want with the custom one
I want to localize the plugin. Can you please help?
Why not! Please look into buddypress-message-privacy/languages directory. You will see a message-privacy.po file. You can translate this file using poedit(or any software you like, I personally love poedit).
Once the translation is complete, please save the generated mo file as YourLocal.mo . Fo example, en_US.mo(for US english) or nb_NB.mo for Norwign.