Hi,
Some of the questions regarding the new calculated metrics are answered in the FAQ here - https://marketing.adobe.com/resources/help/en_US/analytics/calcmetrics/cm_transition.html
Calculated metrics based on Unique Visitor metrics will be visible in the following Analytics components: Reports & analytics, Report Builder, and Reporting API.
However, these metrics will not be supported in the following components: Segments, Analysis Workspace, Real-Time reports, Anomaly Detection, and Contribution Analysis. When you create or edit a calculated metric based on Unique Visitors metrics, you will see a compatibility warning that the metric is not compatible with certain areas of the product.
You use an base Unique Visitor metric on a report with a segment. You can create a Calculated Metric based on a Unique Visitor metric; however, that calculated metric cannot be applied to a report with a segment, nor can that calculated metric have a segment embedded in it.
Hope this is helpful.
Regards,
TM