This is one of the most important part of the sound engineers in Nuendo. And it has been redesigned for their workflow. The workflow is:
Listen thru the project.
Once something is wrong, select the object (Audio Event or Range) and apply any process (mostly EQ preset or Gain preset).
If it doesn’t help, apply the same settings again.
Done, next.
So the Nuendo users have the DOP window open forever.
Yes, you can assign a Key Command to the Process or Plug-in: Key Commands > Process (or Process Plug-in). The last settings of the Process/Plug-in will be applied, once you hit the Key Command. You can also create a Favorites, and assign a Key Command to the Favorites.