Automator is a workflow, so items tumble through it. Here is an example of a single-action or two action workflow that is saved to your Desktop:
Single action (you drag and drop the Jam file on the application icon)
- Launch Automator, select Application, and then click Choose.
- Utilities Library : Run Shell Script action
- Drag and drop onto the right-most workflow window
- Set Shell and Pass input as shown below
- Change the example Safari to Logic Pro X application name. If that name has white-space, then surround the application name with double quotes.
- When you drag and drop the Jam file onto this Automator application, it will replace the "${1}" argument with the full pathname of the Jam file, and hopefully, Logic Pro X will launch to an opened Jam file.

You replace Safari with the Logic Pro X application name. If the name contains white-space, then surround it with double quotes. When you drag and drop the Jam file on the Application, the "${1}" is replaced by the full pathname of the Jam file, and Logic Pro X should open with that file. I don't have the application, so cannot test.
Two-action (not drag and drop)
- Launch Automator, and same instruction for Single Action.
- Files & Folder Library : Get Specified Finder Items action
- Drag and drop the action into the larger workflow window.
- Add your Jam file
- Utilities Library
- Drag and drop the Run Shell Script action to the right-most workflow window
- Use the same settings as the single action example above. Replace the example Safari with Logic Pro X as in the single action. When the Automator application is run the Jam file will fall from the first action into the Run Shell Script action and replace the "${1}" with its full path.
- Hopefully Logic Pro X will launch and open the Jam file
- Save the Automator application to your Desktop where you run it with a double-click.
