Data File Tools

You can use the setting in Tools > Options > Micro Focus > Data File Tools to control the version of Data File Tools that is used as default.
Use Classic Data File Tools
When this option is selected, all actions that invoke a data file editor will use the classic version of Data File Tools.
When this option is not selected, where possible, the new version of Data File Tools is used. This version does not have the full functionality that the classic version has, and so actions that cannot be performed using the new version (for example, using IMS segment layouts) will be carried out using Classic Data File Tools.