When setting up a new project, the key to syncing up your schedule and your Specs & Selections page is to associate your selection deadlines with the milestones in your schedule.
If you are copying items from a Spec/Selection Template and your schedule has the same milestones as the ones you mapped on your template, your selections will automatically copy over with the right milestones.
But, you may have items on your template with requested by milestones that don't match up with your project's schedule.
In this case, you can review the items that don't have decision deadlines at any time by using the "Change deadlines" link at the top of the Specs & Selections page, and reassign items as needed.