Chris - thanks for the reply.

Actually, what you are describing as the "correct" behavior - permitting a message to be composed while a chart is being viewed - is the problem we are having, and we are opening the chart from the right side. When two of our front office users enter a message, they use the patient button as you described (followed by the "Pull Chart" button) not the patient list on the left side. If they attempt to toggle screens between the message and the chart, the message box resets/erases.
For all of the other users in our office, the message is preserved when toggling. The issue with the disappearing messages only started after we upgraded to 10.1.1, and only for two users (and a third new user I created for testing purposes.)
I displayed this for the support team, and they told me the message erasure was the correct behavior. Be happy to show them, or you, again.