Unknown error while loading the Motion graphics template - but different

Issue:
Motion Graphics from the Essential Graphics panel and Premiere Composer (Mister Horse) are not working properly in an older project.

Adobe Premiere Pro Version: Latest version.

Operating System: macOS on a MacBook M3 Max.

System Info:

• CPU: M3 Max
• GPU: Integrated GPU (MacBook M3 Max)

Video Format: The issue is related to Motion Graphics, not the video format.

Workflow Details:
The issue occurs in an older project from 2022 that I regularly duplicate and reuse. When I create a new project from scratch, the Motion Graphics seem to work fine at first, but sometimes they stop working after a while. However, I need the older project to work properly since it’s very large and important.

Steps to Reproduce:

1. Open an older (2022) project that I have duplicated.
2. Try to use Motion Graphics from the Essential Graphics or Premiere Composer (Mister Horse).
3. The Motion Graphics either don't load or malfunction.

Expected Result:
Motion Graphics should load and work smoothly within the old project.

Actual Result:
Motion Graphics don't work in the older project. They sometimes work in brand-new project files, but after some time, they also stop functioning.

I’ve tried clearing the cache, restarting, and reinstalling Premiere, but the issue persists.

Sometimes it works on new created projects and sometimes it does not. 

There have been massive changes within Premiere since the 2022 builds, so having issues with complex graphics is probably not unexpected.

If you are using an older version project file, and allow Premiere to "update" the file, that tends to have more troubles than if you use the MediaBrowser panel to select the old project file, and import sequences to a new project.