Hi
This might not answer your question, but should maybe help you and others.
I have IFTTT/Alexa/Centro setup
How to setup a voice command to Alexa which then sends to IFTTT, which then sends back to Centro 8m, below is an example of sky command, (turn on sky/input on amp etc)
Create applet on IFTTT
If = Amazon Alexa, choose "Say a specific phrase", type in your phrase "sky"
Then that = Type "Maker" click web request
URL =
https://admin:password@your ddna or static IP address/api/macros/sky (sky is a macro I setup on Centro 8m), the password is your centro 8 password.
Method = Get
Content Type = Plain text
Body = leave empty
Create action
Now find out what your Centro 8m IP address is, if it's not a static IP, please change to static. Go to your router and port forward HTTPS port 443. Input your IP (192.168.1.25) whatever you centro IP is. This is allowing the command to be sent to your Centro.
You'll also need to link Alexa to IFTTT.com, which is easy. google it.
Then setup a macro on your Centro called "Sky" and add whatever actions you want.
Few pointer mind you, setup your IFTTT account with double verification (text), also make sure your centro password in very strong. Also there is a few second delay from IFTTT
Hope this helps