I’m not the person that should be answering this as I don’t even have Ecwid, but looking at the documentation you would need something like this in your htaccess file.
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteRule ^shop/.*$ shop.html
</IfModule>
Assuming that your “store” page was called “shop.html”., and you have Turned on clean URLs in your store integration code in the shop.html file. I think @ben had mentioned in the other post that he was going to do a video on this. Don’t know what the ETA is on that.