You're in luck! I built this for a demo a while back. Here's a Twilio module you can import into your project:
EDIT: Please re-download the module. I've updated it with some more in-depth logging.
That blog post you have linked to is a couple of years old, so while it is not incorrect, there have been a lot of new capabilities added to Mendix since then.
Not sure what kind of integration you want to perform, but just out of curiousity, I searched Twilio REST API and got to this page pretty quickly. Looks like you can send an SMS by POSTing to a web service. In Mendix, this would be a trivial task - simply use the Call Rest Service activity in a microflow.
This would get you started....Perhaps you have a bit more information about your use case that the community could consider and respond to.
Hope that helps,