For sending through Twilio on Darkroom,
Make sure Photo To Phone is checked,
And for email, photo to email.


Make sure that the image size is set to MEDIUM.


Sending Boomerang/GIF

Make sure to have the Enable animations, click on settings

On the settings, Click on mp4 and enable Boomerang.





If you're running into issues still make sure your messages aren't being carrier blocked more info on the article below

This article will explain how carrier filtering works and how to work around being blocked

Make sure you're using proper grammar and using caps in the right places.

The article will explain more details on messaging.