Hello,
I suggest to check instructions from this file. They are similar to what is shown in a link provided, though adds more detail.
The wiki example was tested with 7.3 and was confirmed to be working.
It would be helpful, if you could attach a troubleshoot file to your question. Please, replicate your configuration, then access router's WebUI, go to System -> Administration -> Troubleshoot section and download troubleshoot file from there. The logs in the file might provide more insight into the issue.
Best regards,