I managed to keep working with this project without any other issues. And then, after rendering the project for output an hour ago, saving the project and closing Nuendo, on the next restart and opening of this project a few minutes ago, the Workspace redraws went back to their usual snappy redraw speed for no apparent reason! All the GUI elements returned to their normal opening and closing speeds and the project closes in under 10 seconds now too. It also opens faster than it did before.
Really weird, right? I even added more processing and softsynths to the project since I started this thread.
WT*? What’s disquieting is not knowing why this happened in the first place. You can be sure I’ll follow up if it happens again.