You can find a demonstration store showing several customizable products that were all built using the Live Preview Options app:
In this section there are several video tutorial that show how to create customizable products. Watching these videos is very recommended so that you can understand how the app behaves.
Feel free to leave a review for our App on the Shopify App Store. You can give us feedback and contact (provide as much information as you can) us at: firstname.lastname@example.org