csl shortcode broken?

Hi,
It seems that the csl parameter in the shortcode isn’t working. It worked last week, but something changed somewhere. I’ve disabled all plugins, except mendeley to make sure there weren’t any conflicts there and the error still occurs.
Here is what I see on my publications page:
Sometimes it shows the only the years (because the shortcode is grouped by year), and sometimes it shows “Mendeley Plugin Error: 403”. But never the actual biblio. Not sure what causes each to appear when no changes are made anywhere.

When I run the debug I can see the elements are being returned from Mendeley but the csl isn’t being seen. This is the same csl file I’ve been using for about a year and it is unchanged.

For fun, I grabbed a regular old csl file (I think I grabbed Council of Science Editors) and plugged it in but got the same error/display of year.

I’m using WordPress 3.9.2 and the Mendeley Version 0.9.6. And my shortcode is: [mendeley type=”folders” id=”xxx” groupby=”year” csl=”https://MY-WEBSITE/MY-CSL-FILE.csl”%5D

Any help is appreciated. Thank you so much for all your hard work on this plugin!

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