You can look inside the zip file with WinRar and see if the voice has files with csv extension or with lua. "Lua" are newer voices with more features.
For TTS voices with "lua" files inside you need to edit inside the zip file:
Use WinRar and edit the file without full decompression (it will save it back automatically when you finish.
This should work except for Jelly Bean (4.1.1) where NO Voices simple or TTS work with this version of Primo.