ok, Ive managed to do it. It’s a bit of a hack though and I’d be interested in suggestions for a better way.
First of all I created a directory tree – /Database/andy/usr/local/etc/havp/templates/en and copied the contents of /usr/local/etc/havp/templates/en into it.
I modified the html files to suit.
To make the modified files appear, I remounted part of the RO filesystem onto the directory under /Database using the post-boot script, ie;
mount –bind “/Database/andy/usr/local/etc/havp/templates/en” “/usr/local/etc/havp/templates/en”
Reboot and the modified file(s) appear. Obviously you have to copy all directory contents even if you’re only changing a single file as the whole directory gets re-mapped.
As I said, a bit of a hack !