Excuse me for my long delay reply but I'm very busy since last week (rush job work at a same time!).
I have maded a restart service of ISPConfig and also a server reboot. After, I have maded again another SSL request but I have the same thing... no SSL.
I have tried to delete certificate and remake a "Create" but the SSL Request and SSL Certificate textform... and it's ok!
Well it's important (I think) to restart the ISPConfig service after installing the package. And made a Delete Certificate and recreate the certificate after all.
Thanks Falko continue your good work!