Inserting foreign language characters-Guttenberg

Hello. I need to insert foreign language characters (all unicode) into guttenberg blocks. Before guttenberg, all I ever did was edit the language in a native word processor (Greek, Latin, Hebrew, Arabic, etc) and then cut/paste the text into my document. Since the change to guttenberg, when I do this all the foreign language characters show as ????

If there is some place in the Codex or other guttenberg instructional material, I would appreciate a pointer.

Thank you!