App Studio 2.5 brings a new dialog box: NSB.ShowProgress. Here’s how it looks:
It floats above your current screen. You can put any message into it that fits. It can be dismissed by your app or by the user.
Here is how to put up a message:
NSB.ShowProgress("Please wait...")
and how to dismiss the message:
NSB.ShowProgress(false)
You could also issue multiple NSB.ShowMessage calls, each time updating the text in the box. This is useful for length operations. You can keep your user advised as to what is going on: the perceived waiting time will be reduced.