If you run into problems it might useful to run the forwarder in debug mode. It will output verbosely if connections are sucessful and data from the EmontX received as normal.
1/ Connect to the EmonWRT with SSH. Use Putty program if you are on windows. If using Linux just open a terminal. User is root and default password is admin.
2/ Stop the forwarder service like so
$ /etc/init.d/emonwrt stop
3/ You can now run the process manually like so:
$ /usr/bin/emonwrt_forwarder.sh -d
The forwarder will run and output debuging information in the terminal. You can stop it anytime using the Ctrl^C.
4/ You can then start the forwarder for normal operation again like so
$ /etc/init.d/emonwrt start