Oh my. I think that's "normal" for any zip that contains an exe file. Still, just to be sure, run a virus check on it and if you still don't trust it then of course do not run it.
Downside is, I wasn't able to make HTML5 export work with my projects after wrestling with it for a week or two. I may continue to try to make it work still, but I will need a massive amount of time for that (I have to start from the bottom up to see where it goes awry). Should I succeed, ther will be a browser version for this project too.