This article talks about the issue with Atlas Recall not loading on the Developer Beta of 10.12.4
UPDATE: If you are experiencing this issue with macOS 10.12.4 beta 1, please update to the latest version of macOS (beta 2) as it resolves this specific issue.
If you are running the macOS Developer Beta (most recently 10.12.4), you might experience issues with launching Atlas Recall.
The effect might be a blank window in Recall with no text, and no ability to quit the application.
If you are experiencing this issue and have additional questions, please contact us at firstname.lastname@example.org