You can do it in the new version without scripts, but it is different than in the old version.
In the new version, you start by creating a new icon. Then you add or remove formats and save the icon as .ric (it may be empty).
Then you go to Tools->Application options and to the Icon tab. There you click on the Add... button and locate the saved icon.
This adds a new icon template that you can use in the batch image->icon operation, when creating new icons or when switching templates.