To be visible in the EXS24 mkII Sampler Instruments pop-up menu, instruments must be stored in the Sampler Instruments subfolder of any of the following folders:
~/Music/Audio Music Apps: User-defined or edited instruments are stored here.
/Library/Application Support/Logic: Factory-supplied sampler instruments are installed here.
…/ProjectName: Logic Pro X also searches for sampler instruments in the project folder.
Search by project is included for backward compatibility with existing projects.
If you use the Save As command, old project files and folders are converted to project bundles. The original files are not changed.
If you save a new project, sampler instruments and samples are saved with the project bundle.
Note: You can store your sampler instruments in any folder on any connected hard disk. Create an alias pointing to this folder within a Sampler Instruments subfolder (using any of the paths listed above), and they are shown in the Sampler Instruments pop-up menu.