While various persons have gotten off track on this question, the problem with 4 wheel down towing never was the transfer case...after all, splashing oil is splashing oil, but rather with the steering system!
The steering is electric over hydrolic and Mazda wasn't certain that flat towing wouldn't ruin it especially under warranty. So when in doubt....advise against !
We'll be waiting for your towing experiences ...

 

any new updates on this subject?

 

I towed my car from Austin, TX to Lawton, OK once, but I used a complete car hauler that kept the whole car in the air. Just didn't want to take any chances.