Accessing PC Interface via LAN Router

[presage]

I am trying to connect to 2x 6620 robots remotely through the PC Interface.  I have a eWon 2055CD industrial LAN Router connected to the internet on a fixed IP address.

I can access the robots via my laptop when directly connected onto the switch side of the router and see both robots and PLC, but when I try to access via the internet through the LAN Router's  VPN tunnel, I can only see the PLC.  I can't even ping the robots!  I have been trying to get this setup to work with help from the eWon rep with no success yet and time is running out.  I have tried mapping all the necessary ports mentioned on both TCP/UDP/FTP mentioned in the ABB documentation,

1.  Has anyone out there managed to successfully work a eWon with ABB (I know ABB use eWons for their own remote diagnostic service).  How do you do it?

2.  Has anyone used an alternate vendor (rather than eWon) successfully to access the PC Interface via internet VPN?

Cheers