06 Workaround 1
As Rafael has established, the issue occurs if the viewer window is open when you edit an image. He suggests launching the plug-in from the browser window only, so that the viewer is not visible at all.
I tried this, and it works perfectly. The thumbnail updates fine in the browser window, and if you display the viewer, it displays here too.
07 Workaround 2
And here’s another workaround I discovered. You can also swap to full-screen view and launch the plug-in from there. Both the thumbnail in the pop-up browser panel at the bottom, and the preview in the main window display perfectly.
08 So what’s the answer?
I don’t know whether Apple has caused the problem or Google, but hopefully one of them will fix it shortly. In the meantime, Aperture will work with the Google Nik collection, but ONLY if the viewer window is NOT displayed when you launch the plug-in.
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