Problem

How to rotate view while using a tool and return to active tool without pressing an extra key or button?

Solution

Shift + XButton 1 (Middle button) drag

In the default setup, dragging with Shift + XButton 1 (Middle button) will rotate the view until the button is released and then return you to your active tool.

You can configure MicroStation specific button assignments in the Button Assignments dialog from the Workspace menu.