If you can get FocusMax's AcquireStar to give consistently good focus, then ACP should be able to use FocusMax consistently, too. That's my experience anyway. Test this with FocusMax's AcquireStar button, not the Focus button.

Be sure you're tuning FocusMax to your telescope system by adjusting its Preferences in FocusMax's AcquireStar tab.

This assumes you have activated AcquireStar within ACP Preferences.