I have also added the filter for acquisition date. If I use that to select 'in past' '60 Days' that will then only pick up the people who have been added into the nurture in the past 60 days and the 'no score change' filter will pick up the contacts with zero score change.
Hi Jennifer, are your leads added to the nurture program on the day that the email address becomes known? If yes, adding a filter that the acquisition date needs to be older than 60 days would work. If people can also be added at a later stage when they are already known in Marketo I would suggest to create an "Added to nurture" field that you stamp when the person is added, so you can use that field instead.