Sorry for the lateness of this post – life intervened. 😉
The process I have been using to make Motion 5 filters available in FCPX is as follows:
1. Open Motion 5
2. Select “FInal CUt Effect” from the Project Browser to start a new Motion project
3. Click on the “Add filter to selected objects” button to bring up a list of all the filters you can use. It is located just below the viewer. Select the filter you wish to use in FCPX. For this example I chose “Color Correction –> Brightness”
4. Make sure the filter is selected in the time line and click on the “Inspector” tab in the upper left region of the GUI.
5. Make sure the “Filters” tab is selected. You should see the parameters for the Brightness filter.
6. At each “level” of the rigs at right of the filter you will see a drop down menu if you hover the mouse over. In the drop down list you will see the option “publish”. You must select this option for whatever rig you wish to expose to FCPX.
7. After you have selected the controls you wish to publish select “Save as” in the file menu. In the dialog you will need to name the effect as it will be seen in FCPX, and create a category if there is not already one created. I created a “Motion 5 Color Correction” category, unclicked “Include Unused Media”, and then saved the project.
After this is done you will immediately see the saved project in the FCPX effects browser, and can use it as any other FCPX effect.
I hope this is helpful.