Florent, why Zope Product would require Localizer to be installed to
function correctly? We've just removed all gettext form .dtml files to
make it work. ZMI is mainly in English and that is pretty good solution
until Zope provide Basement for Product l10n. Until that time I see no
reason to force users to install Localizer just to see ZMI of that one
product (NuxDocument in our case) in other language. Note, there is no
fallback mechanism to make it work without Localizer installed.
Feel free to write one, it will be included in the next release. If you
don't, it's in my TODO list for the project.