Import data with connections

My data design allows multiple Entry records to one Member (user) role record. Member has name & email fields; I assume email is the primary 'key' since I can't create >1 entry with the same email. Two questions:

1) Is Knack storing a foreign key in its 'internal' Entry table back to Member, so that if my users update their name & email later, the connection is not lost? That appears to be the case, just want to make sure.

2) Is there a way to modify the u/i so that I can use something in addition to Member: Name in the connection dropdowns? Member:Name (first + last) is not unique, so it's very difficult to pick the correct Member.