Thank you NTolerance
I was mounting my NAS (Qnap) using a bookmark but this way is much more reliable.
I followed your instructions and created file mount_neptune.sh in my user directory.
My problem of being able to save files from firefox and other apps into my nas, this was solved by michaelzap's suggestion of using "ln" on the second line.
ln -s /home/brian/.gvfs/"public on neptune" /home/brian/neptune
I would suggest adding this to the bottom of your very excellent tutorial.
Thank you both again.