Updgrade from 7.3 to 7.4

I have just upgraded my development machine from 7.3.4 to 7.4.2 and have a
couple of small questions which I can't find any answers to in the documents or
history.

1) What does the TRIGGER group/user privilege mean when applied to a VIEW?
(after the upgrade all groups that had access rights to views now have the
TRIGGER option too)

2) One of my queries does an ORDER BY on a column that is of type BOX.
This query no longer runs and returns the following error message:
ERROR: could not identify an ordering operator for type box
HINT: Use an explicit ordering operator or modify the query.

The only things I can think of doing is splitting the box out into the four
separate values, but how do I do that with a box?
my_box[0] returns a point and my_box[0][0] is not recognised (I tried various
other forms but to no avail).

Any help/hints would be appreciated.

Regards
Donald Fraser