I don't mean to sound like a dick, because please believe me I'd so much rather use a decent made-for-Mac BitTorrent client than the crappy half hearted ports with awful UI and poorly thought out config, that seem to be nearly every other client. But Transmission hasn't supported any of the last two routers I've had, and there was another patch of a couple years about six years ago when the same was true. Likewise the router I had about eight years ago. It is disappointing to have such huge patches of incompatibility, and now that I'm on fibre and must use my ISP supplied router, I cannot swap hardware just to get to use Transmission.
Yes, I know I can open and forward ports, but I move from computer to computer, occasionally also moving laptops to other networks such as at family and friend's where I don't have router config access, only the ability to open a port via NAT traversal. And about half the routers I encounter in the 'wild' are not supported by Transmission's NAT traversal
I really need Transmission to just handle NAT traversal on it's own, like other clients I've used.