Have installed Neo Speech French voices but it does not work in Captivate…

I have installed NeoSpeech French voices (Louis and Roxane). They appear clearly in the Windows Settings but as I try to use them in Captivate  (Roxane or Louis), I only hear the Microsoft Voice. So I made a test. When I change the voice in the Windows Settings and choose Roxane (as below), what ever voice (Roxane or Louis) I choose in Captivate, it is Roxane that I hear. Any tips on how to successfully hear the two voices?