ERROR: "Access violation at address 0000000000000D244E6 in module 'TDM.exe'" when modifying data type conversion settings (4322837)

Modifying the Data Type Conversion Settings in expert mode displays an empty dialog box and then throws the error message: 
Access violation at address 0000000000000D244E6 in module 'TDM.exe

Replication steps:

- Open Toad Data Modeler | Settings | Options
- Enable Expert Mode
- On Expert Mode | Expert Mode settings | Data Type Conversion Settings window.
- Set source: MS Sql Server 2014.
- Set destination: Oracle 12c.
- Click Load button.
- On Source column, select Integer.
- Define a value for Param1 and Param2 columns for the Integer row.
- Click OK. Access violation error received