Hello andy,
First question dos it work internal (on the local network) ok.
If not gif more right's to the user how can do is in de PHPMyadmin module.
Suggestion:
Make allways a separate user how can's only connect from a specified Ip adres so your securiti stay's on a high level.
It works on a standard SME 5.5 box on my location to connect from outside to the MySql database.
Goodluck
Johan