1. Open In
Selecting the Open In Checkbox allows you to select which application will handle the exported IDML file.
2. System Default Application
This is the default application your macOS system uses to handle IDML files. If you have InDesign loaded, the latest version of InDesign is the most likely program the macOS will see as the Default Application to handle IDML files.
3. Specific Application Path
Selecting this radio button will enable the selection area.
4. Selection area
Click in the selection area to bring up a Standard macOS Finder window allowing you to navigate to the application you wish to use to handle the exported IDML file. The application you select must be able to actually handle the IDML, otherwise it will display some form of error message. Some possible choices for apps would be Adobe InDesign or QuarkXPress 2019.
5. Show in Finder
If this box is checked, when you perform the Export as IDML action, once it is completed, your file will be revealed in a Standard macOS Finder Window. Unless you need to interact with the file immediately after export in the macOS Finder, this box should be left unchecked. Leaving the box unchecked will also speed up the export process as a Finder Window will not need to be called and displayed.
6. Close Document
If this box is checked, your file will be closed in IDMarkz after the IDML file has been exported. By Default this box is left unchecked and your file remains open in IDMarkz until you manually decide to close the file.
7. Cancel Button
Clicking the Cancel button will cancel the IDML export action and close the IDML Export Pane. This will take you back to the main File View Window in IDMarkz.
8. Export Button
Clicking the Export button will export an IDML of the currently active file using the settings you have selected in this Export IDML Panel. When you click on Export this will also bring up a Standard macOS Finder window asking you where you would like to Save your IDML file.