Unable to Switch Database Connections in Toad Workbook

Toad Data Point 5.3. When opening a Workbook developed by another user, Toad Workbook is unable to switch the connections. Even though the correct connection is selected, the Workbook always reverts to the original connection.

Anyone else encountering this issue?

Need a resolution ASAP as SR is taking too long

This issue is discussed here: TDP Workbook 5.3 database connection error - #2 by Gary.Jerep

We downgraded to TDP 5.2.1.299 to get around this issue.

This is still happening in version 5.7.0.405. Is there a work around or a way to save the workbook without a connection? Thank you.