Theme is broken. Fix it and release a working version.
Took me days to figure out what the issue was (on my own). Very frustrating when you finish website and it's not functional. Support was slow (4+ days to get a reply in their support system - and only after I mentioned that delay in the comments on ThemeForest) and not very helpful - shifting blame elsewhere: plugins, device, etc.
I had a light-bulb moment today. Had to turn off all animation to make the site functional. But I work with websites on a regular basis...
What about people who aren't tech enough?