The Viper client doesn't see that the VPN is connected and working. This happened using version 0.9.3 on a Windows 7 system. The configuration is via an OpenVPN certificate.
Connecting via the Viper client works fine. Checking the IP address that is used verifies that the VPN is working.
But the Viper client still says that it is offline and shows an open lock. It is not possible to disconnect via the Viper client, since it doesn't know it is online. You can only connect (again).
Quiting the Viper client disconnects the working VPN.