In AdvancedInstaller it's possible to customize file using the Permissions Tab of the file or folder properties dialog. This is not available for INI files created using the INI File Dialog.
How can I customize INI file acces permissions?
As stated in this AI community posting this is not directly possible. But there is a workaround to accomplish it:
In order to customize permissions for Application Folder\myApp.ini created using the INI File Dialog, create a new physical file with the same name in your filesystem (e.g. c:\installer\myApp\myApp.ini).
In AdvancedInstaller add that file to the same folder where your myApp.ini already resides in: Application Folder in this case. Skip the INI import functionality.
Now it should look like you have two myApp.ini files in your Application Folder and you can edit all the file access permissions on the imported myApp.ini just like you do on any other files or folders.
These customizations will be applied to the installed myApp.ini on the target machine.