We had it on 4.0 and still on 7.13. We have it run over the VPN.
The firewall was not the problem for us, we have found that the actual user account has to have admin rights to set the adaptor settings etc. Even though a user without admin rights can change it and it appears to work the traffic appears to jump to other adaptors (silly as it sounds).
Give the user admin rights, log on as them change the adaptor and all the other settings as required, log out thus saving these settings for that user, then remove the admin rights for the user.
We have 120 IPC users and tested it so far on 5 of them and it has worked for everyone of them so far.
