You are right.
I enabled custom-fields support for custom post types and now I can see the content of the custom fields imported in the translations.
At this point the issue is only related to the Type plugin I mentioned.
Even if the custom-field value is populated (I can see it in the original custom fields box), the value is not imported in the custom fields interface showed by Type.
I will investigate.
Thank you Chouby!
rob
is it just possible to copy the content of custom fields while translating custom post types?
or pll_copy_post_metas() works only with posts and pages?
rob