Thank you so much for using our theme.
1. To create variation with images swatches you need to go Products->Attribues, create some attribute and then create attribute’s values. Inside of this value you will see two fields “Image preview for this value” and “Color preview for this value” that will add swatches to this attribute. Than you just need to create variable product and use the attribute for product variations.
2. You need to enable Visual Composer for products in admin panel -> Visual Composer -> Role Manager -> Post Types and check “product”. Then you will be able to add custom content with VC while editing product into “Description” field.
3. Thank you for your report. We will find the solution to the iPhone bug and fix in the future updates.
Thank you and hope this will help you.