Kiwi2005,
The problems with the speech files in your mod is because the .ogg files must be in mono format. Using stereo files will cause game crashes.
I've tested it by converting some of your files to mono, and it works: I can put them in all folders 1-9, so all voices are using the new speech files.
Credit goes to Payoff

for pointing this out to me (
see thread here)