I attempted to login using the details you provided above, but it would not allow me to login using those credentials.
Is your Pro dashboard page set as a parent page?
I can see in the screenshot that it has the shortcode [wcv_pro_dashboard]
Try also saving your permalinks: wp admin > settings > permalinks
Also, which Add Product button are you clicking on when it takes you to the 404 page?
If you provide me with an admin login & password in a private reply, I can login and take a look..