The default device for VCD is /dev/cdrom. If your VCD is not this device, choose your device in the option dialog or use the command line :
In command line, you can specify a track like this :
The default track is 2. You don't need to mount your VCD to play.
Now, you have full control of your VCD. Warning, when you seek the VCD, there is a little time to wait before see the result.
Warning : Don't try to mount your VCD and read the data file. It will not work. Use only the open VCD option.