How do I know who is the current borrower of a title ?

If you need to know who is the borrower of a title, activate the title, then choose the Linked records command. In the following dialog box, choose Loans. Either you get the loan record with the borrower name, or you get a message No records found, meaning that the title is not being lent.

If the option Display the borrower has been checked in the Options of the Loans file, then you only need to double-click on a Title and to display the Copies tab in order to get the borrower's name.