Arduino Bluetooth and EasyVR Shield compatibility

Hello. A beginner here. I'm having problems trying to make an Arduino Bluetooth and EasyVR Shield work together. As for now, the shield is inaccessible. The default approach, that is trying to connect via EasyVR Commander when the jumper on the shield is set to PC connection mode, resultis in " Could not open the port "COM16". There is no process on the other end of the stream " error (the port number is ok I think, it worked fine in a few test sketches). The other option - running a provided bridge sketch on the ArduinoBT and the jumper set to SW (Software serial mode) fails with " Could not detect device connected to port COM16 " error. So my question is - could this be caused by the ArduinoBT architecture (probably using the same 0-1 pins for communicating with the Bluetooth module and the shield), or is the EasyVR Shield at fault?

P.S. I'm using a 3.5V power supply. Both Arduino and EasyVR's recommended operating conditions state that the min voltage input is 3.3V, but could this be the cause?