Is there any particular reason you're not wanting to use Auctiva? You can schedule your listings in the lister if you wanted.
In my experience, the Mac-based programs aren't very good when it comes to customization (e.g., custom templates). Of course, neither is TL. Blackthorne (another PC program) is pretty versatile. But, then again, it's not free and it's PC only.
As far as I've been able to find, Auctiva is the only lister that even comes close to Blackthorne and you're able to use it with a Mac. You can use custom templates, you've got free scheduling and image hosting, and you get a Store Window that shows the other items you have for sale. Those are just a few of the things you get and they're all free.
So...if there's a specific reason you're wanting to use something else, I'm wondering if Auctiva doesn't already do it. Why pay for something when you don't have to?