I'm following a well written tutorial written by @andymahood__c: http://www.tquila.com/blog/2014/11/17/setting-lightning-connect-and-your-first-external-object

When I get to the step #3 ... "Select Edit on the CustomerID field, ...", I don't see Account (or any objects to relate) listed in the drop down box. I have created the custom field on ACCOUNT named CusotmerID Text(5) and marked it as External ID as follows:

CustomerID CustomerID__c Text(5) (External ID) [Checked]

Any ideas?