Hello @10400991,
Thanks for the question. Yes, the functionality of creating custom .mogrt files for Rush is no longer available. This is a user-to-user forum, so the answer to your question is not available from anyone here. I will let the product team know you are still looking for that feature. I'll also mark the discussion as a feature request for you. I would also like to see this feature return. Sorry for the letdown.
Thanks,
Kevin
Kevin Monahan - Sr. Community and Engagement Strategist – Adobe Pro Video and Audio