I have a host who set up our Juniper SSG 5 VPN with Firmware version-6.2.0r5.0

I've been trying to set up VPN on it using this guide: http://kb.juniper.net/InfoCenter/index?page=content&id=KB4094 I've followed the steps and on my Mac, whenever I try to connect using L2TP over IPSec I get the following error;

Summary of Steps: Create User (give them L2TP auth ability), Create Group, Place User in Group, Create VPN Gateway, Create VPN, create IP Pool, change default L2TP settings, create Untrust > Trust Policy.

The L2TP-VPN server did not respond. Try reconnecting. If the problem continues, verify your settings and contact your Administrator.

I looked in my Firewall's logs, but I don't even see anything under Reports > Logs > Events.

I'm.. obviously missing something, I just don't know what I'm missing at this point. I'm just starting networking and this is sort of Step 101 and I'm getting annoyed and just want to throw up OpenVPN, but I've read that has problems with Juniper Firewalls. Hooray.