Cannot Save Preferences (10.9, 10.8, 10.7, 10.6 users)

Clicking the Save button in the Preferences window causes Amphetamine to hang. Some users may also experience issues trying to activate Amphetamine for custom time periods. This is a known bug in version 1.5.3 of Amphetamine, and the bug is corrected in version 1.5.4 (currently awaiting review by Apple). While the App Store version is waiting for approval, you can download a copy of the the updated version with included fixes here:

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