Setting your number to forward straight through to your number/device without a main greeting is simple.

Create an extension with the desired forwarding number. Make sure the forwarding numbers "Forwarding Options" are set to "Calls will connect to you as soon as you pick up."

Now you need to go to "Your Numbers" under "Settings".


Set the simple forwarding number's "Forwarding Options" to "Transfer to extension..." and select the extension.