"Every time" if you want to play it every time a caller is going down if te Flash Message is activated
"On condition" if you want to play it in the case where the call concern a particular context key ( = Label):
choose the "Label" ( = context key)
write the audio message to play to the callers, try the audio with the player in order to listen the message
you can choose to send an SMS to your caller by choosing "send" in the dropdown :
Sender name: allows you to choose the name displayed on the SMS received by the caller
SMS text message: is the text that will be contained in the SMS received by the caller. It can contain several information included during the call by using existing context keys and added to the context (thanks to Set & Update Actions for example).
Complete documentation (from script to the activation of a FM):