Hi Paola,
Thanks for considering Auto-Complete :
1. Yes, any Task is considered, regardless of whether they are tagged as a milestone. Instead, you choose a Task Category (e.g. "Auto-Complete") then select the Maximum Task Length (e.g. 0 mins to 10 mins). Run it find and update as Complete every WorkFront Task within that Category that matches, providing their predecessors are all complete.
2. Yes, you can manually run whenever you wish; alternatively, you can schedule it to run automatically (under My Account > Scheduled AtApps).
3. Yes, the cost is per WorkFront Task updated, but with no charge for a Task that is already marked as Complete. When you join AtAppStore , we include a complimentary amount which you can use to try out Auto-Complete. Once that runs out, you can add funds as needed. We also offer a number of annual prepayment discounts ranging from 15% - 90% off, based on your expected usage, which I'd be happy to explain offline.
Regards,
Doug