Help setting up VPN PPTP on 3500L

Using the latest 18.7.10 big beta firmware

Followed these instructions: 

http://www.dd-wrt.com/wiki/index.php/PPTP_Server_Configuration#PPTP

When I try to connect, it eventually times out verifying username and password.  This is a bit further than I was getting, so I assume Ive got forwarding etc setup correctly.  Displays Error: 

I have my router connected to my adsl modem/router and setup as follows.

ADSL router 192.168.1.254

Forwarded ports 1723.& 1792 to th WAN address

WAN interface 192.168.1.64

3500L IP  192.168.2.1

Also forwarded the same ports to the 3500L IP

PPTP Server IP  192.168.2.2

Couldnt find the Loopback address that I have read needs to be disabled, but I think this issues was fixed with later releases.

Cant find any logs on the router to see if they can tell me anything...

Anyone got any advice???

Thanks