Error type: "Bad Request". Error message: "API Key not found. Please pass a valid API key." Domain: "global". Reason: "badRequest".
Did you added your own Google API key? Look at the help
Check in YouTube if the id UCwKS2U-DwjPZZvM6mSXPKgA
belongs to a channelid. Check the FAQ
of the plugin or send error messages to support