Hi April,
Thanks for reaching out to us! I’d be happy to help you 🙂
Since you have the most recent version of that extension (2.1.0), it should normally work (I tried this extension locally a few minutes ago and didn’t come across a similar problem).
Can you make sure you are using " and not ” in your shortcode?
Also, can you make sure the venues you want to list have thumbnails attached to them? (it’s better to double check as weird things sometimes happen with WordPress…)
Let me know how it goes.
Cheers,
Jeremy