Rick:
I am using the most current versions of OE & AR (OE8.1E 111215 & AR9.0C 120224).

I am able to update the Ship-To's as you indicate, but they do not come to life while I am in the current Order. I have to first close the Order and restart it to see the update.

I tried it under two separate instances:
1. Customer with no Ship-To's: I added a Ship-To (by using the Customer button) but it does not appear in the Ship-To field in the Order
2. Customer with two Ship-To's: I added a third Ship-To. Here it is even a bit buggy. When I returned to the same Order, Ship-To # 1 and 3 are displayed, but the older #2 is not displayed. (Where did it go?)

In both cases, only when I close the Order and restart it are the new Ship-To's appearing.

You try it.