Can't get Google Calendar integration to work…

Hey everyone,

Thanks in advance for the help!

Loving the appointments plugin so far, but can't seem to get the Calendar integration working…

[Appointments+] The following error has been reported by Google Calendar API:

exception 'Google_AuthException' with message 'Unable to sign data' in /htdocs/wp-content/plugins/appointments/includes/gcal/auth/Google_P12Signer.php:67

Recommendation: Please double check your settings.

I have tried 3 separate times now to go through and follow the video. I'm about 99% sure everything is set up correctly, and I've tried just about every combination of solutions I could think of. I can't figure out what's wrong here.

Any help would be appreciated,