For the 'Is US Based' - I see I was not alone and have a solution that worked for me to try.  

First I went to 

• Data Streams > your Lead data stream > Data Mapping. Then I disabled 'Is US based' from the lefthand column. 

After that I refreshed and went back into it:  

• Open Data Cloud > Data Streams > your Lead data stream > Data Mapping.
• In the right pane (DMO side), find the attribute you mapped Is_US_Based__c to. In the left pane (source fields), find the Is US Based column that shows Disabled.
• Reconnect it: either
  • Toggle/enable the existing mapping if the UI shows a disabled switch, or
  • Remove the disabled mapping row, then click the source field and the target DMO attribute to remap them.
• Click Save & Close.
• Back on the data stream, click Refresh Now and choose Incremental Refresh. Wait for Last Run Status = Success.
• Reopen your segment builder so the attribute catalog reloads.

If the UI won’t let you enable it:

• Click Edit on the data stream and step through the wizard to ensure the field is included in the selected object.
• In Data Mapping, click Select Objects and confirm the DMO that holds this attribute is selected.
• If mappings look corrupted, use Remove Mapping on that attribute, Save, then add a new mapping from scratch and Save again before refreshing.

#Trailhead Challenges