Mcrypt is installed, but error implies it's not.

Like I said, do not own a mac, never had actually, so I don't know about this issue. All I know it is weird, tried setting it up for a coworker.

May I suggest using a VM for developing? Take a look at Vagrant, and http://puphpet.com
It will help you with issues like this, and also isolate your development environment, but don't worry, you still write your code as you did before.

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