Hello,
What about the solution when the translators have not got the permission to create any document? Then when the basic document is published, administrators create copies to other cultures and translators may start translating.
You could do this process manually (then you may select the appropriate cultures which you need exactly) or automate it by custom Workflow handler (
http://devnet.kentico.com/docs/devguide/workflow_handler.htm). You could use the OnAfterPublish method, check if other culture versions exist. Unless so, you may create them by API.
Best regards,
Helena Grulichova