To be able to record a call Plus! for Skype detects there is a call and, if set that way in settings, will prompt you to ask if you wish to record. When a call is detected the record button will become red (well, the icon inside the button will) and when recording the button itself will flash green.
Is the record button in the toolbar flashing? It should flash green just like in the image on
Plus! for Skype Features page. If not flashing then you are not recording.
If you stop recording you should see a prompt that the video is being encoded after which the video will be in the video recordings folder. Can you check if there is a video there?
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