I’m going to add my experience with this issue as well just to possibly help with the troubleshooting, as I’ve been messing with it literally all day.
After messing with it on the primary site I wanted it on (that was built over a year ago and we’re ready to launch…but now…well…THIS), I finally moved over to some newer sites to see how they were being affected with fresh new installs of Essential Grid.
I tried it on both a newer install of two sites, one that had X theme installed and one that had another theme on it. Essential Grid did pretty much the same thing–which is, when you go to the Item Skin Editor and look at the skins from around page 3 onward, you’ll see their coding is jacked up on a lot of the skins. I imagine this is a symptom of whatever the grander issue is that’s causing the grids to mess up and not interact the way they are supposed to. I just tried on another site updating everything (including Wordpress), except Essential Grid, to the current versions. Everything is still working as intended on the frontend, but on the backend, the skins are weird again and I dare not mess with any of the settings for fear it will mess up the layout. Now, keep in mind, none of the three sites I’m talking about have Slider Revolution even installed, so the issue must be rooted in Essential Grid. Though, I will point out that even when I deactivated Essential Grid on the primary site I was working on originally and started trying to do stuff on Slider Revolution, even it was doing some odd things (mainly, the frontend was not showing some text layers).
SO, all that said, my guess would be that Themepunch hasn’t updated their plugins to work with the newer version(s) of Wordpress. Please let us know, though, as soon as they seem to fix things. I have a customer that I was prepared to build their site basically around this plugin.