Hi Gordon,
I see your active license account here and I can help you sort this out.
Can you please paste the server error that is occurring? We can easily debug it with that information on our end.
We have used MyStyle with storefront plenty of times, no issues. There are currently Storefront site themes using it that haven’t reported any problems yet, but that doesn’t mean there aren’t any.
For example, what version of Woo Commerce are you using? I know that WooCommerce 3.0 was shipped by WP with LOTS of bugs, and, they changed magic getters which broke lots of plugins on the web, but our latest update for MyStyle is compatible with those changes.
Can you paste your full WooCommerce diagnostic for us to check? That will have all of your exact plugins and versions numbers to see if there is any clues as to what’s messing up your system.
Which host do you use?
What’s your website URL?