I recall that fiasco, Gav - Customs think they are above and beyond anyone or anything. But you raise an important point - you must know the "lingo" and the process - or you pay a Freight forwarder to "translate' it all for you and charge you a small fortune for the privilege. But that is another "finger in the pie" and another piece of the puzzle that must fit in with your objective. Another point of failure as well.
Common theme - FIND the right Freight Forwarder. They don't like dealing with the "personal" containers that much, so you have to look around. If you import several containers, then it is a lot easier. I'd say after 3-4 containers, you can be confident that you have the process "down pat".