If you'd like to remove a recording's association from a specific release in your catalog, you can do so by removing the corresponding track from the release. Here's how to do that:

1. Navigate to the Releases tab of the catalog or playlist folder that you're in.

2. Double-click a Release to open it.

3. Click Edit.

4. Double-click the track you want to remove.

5. Click "Delete Track".

6. Check the box next to "I understand" and then click "Delete Track" again.

Note: this will NOT delete the recording from your catalog - this will only remove the recording's association with the release.