Title template published in Motion 5.2.2 not showing in FCPX 10.4.6

Do I understand that I could store the templates wherever I want and the handshake between the two apps would include the file path?

No, templates cannot be stored anywhere — Final Cut only has a few places it will look:

Inside the Application (DO NOT attempt to place a Motion Template file inside the Application package.)

There's a location that can be used that will be available to ALL users. It is not an Apple recommended location, so I won't specify.

Motion Templates *for* Final Cut need to be created as specific project types (Title Generator Effect or Transition).

Regular Motion projects are saved as "Compositions". Compositions can be saved anywhere — it really doesn't matter, but if you don't specify a custom location, they will be saved in /User HOME/Movies/Motion Templates/Compositions/[Category]/

All Templates destined for use in Final Cut will be in /User HOME/Movies/Motion Templates/[Effects Generators Titles or Transitions]/Category/[template name]/

Final Cut will read these template directories and place the templates into the individual "browsers" organized by the Categories it finds.

Motion 5.4 introduced a feature that would allow you to convert Motion Projects into the different template types. Motion 5.2.2 will not have that feature, you will have to try to rebuild your composition projects by copy and pasting their contents into template starter projects.

If you have Final Cut 10.4.6, you can run Motion 5.4.3 and the templates will be compatible and you will have the converting feature available.

You might find this useful:

https://fcpxtemplates.com/installation-faq/

https://fcpxtemplates.com/installing-plugins-for-fcpx/

Motion 5.4.0 was the first update to have the Convert Project To... menu option. It will be available in 5.4.1.

You can convert a Composition to a Generator in any version of Motion 5:

Go to File > Publish Template to make your project available to Final Cut *as a generator*. You will be asked to choose or create a Category. Make sure you check the Publish as Final Cut Generator is selected. You do not have to provide a Theme (and I recommend you don't until you understand the structure better).

[An *alternative* method:

You can also move a Motion file (.motn) into Generators to make it available to Final Cut. You MUST do the following:

Create a Category folder inside the Generators folder if there isn't one to choose from. Category folder names should have something to do with the content or purpose of your Motion Project so there is some "relatedness".

You MUST create a folder for your Motion project and it MUST have EXACTLY the same name (case sensitive) as the project file (without the .motn extension!)

You MUST place the Motion project file inside the folder with the same name.

MOVE the folder with the Motion project file INTO the Category folder inside Generators.

Final Cut should recognize it has been added and you will find it in the Generators browser under the category name you provided.

HTH

PS — Generators can function just like Titles (as long as the Title Background element is not needed.) You have the same access to Text editing functions in the Viewer as well as access to the Text Inspector in Final Cut.

If you want to, or need to stay at High Sierra, you should consider updating to 10.13.6.

Compositions do not show in FCP. You either export a Quicktime movie from Motion and import it into FCP, or you do as Fox indicated and copy the contents of your composition into the appropriate type of template-probably a Generator, or a Title.