Hi Alex,
Great question! I personally have not tested our plugins with ESS Grid, nor did I see any other threads about it.
That said, I would suggest downloading The Events Calendar which is completely free. It’s the basis for all our other plugins, so if it works with ESS Grid, then chances are that it works with the others.
I’ll also note that all our products come backed with a full refund within 30 days of purchase. That would give you a good amount of time to test things out and return them if they do not work for you for any reason at all.
Does this help answer your question? Please let me know. 🙂
Cheers!
Geoff