Oh no! If your options are missing from the cart page, there are definitely some steps we can take to fix this.
Cart Page Missing Snippets - Legacy Installations
If you're not using the Setup Wizard (which is highly recommended to use for future quick updates!) then the most common cause of this issue is that your theme is missing cart snippets. Please see our installation section to ensure that the app is installed into your shop's theme, including the cart.liquid snippet.
If this snippet is installed properly, please view our document on AJAX themes - this most likely affects your theme.
For Wizard Activated/OS2.0 Themes
If the options are missing for themes using our Setup Wizard or if you use an OS2.0 Theme, ensure you enable Ajax Mode, you can learn more here: Ajax Mode and Product Customizer
Checkout Page Missing Options
Unfortunately we can't force the display any of the Product Customizer options on the checkout or order received pages, as Shopify does not allow apps to make changes to these pages.
With that said, Shopify began adding line item properties to checkout in September of 2015, so your store should support this and display Product Customizer options here. If you do not see your options at checkout, Shopify will need to perform a manual update to your store. Please get in touch with their support team to ask for an update to your shop to display line item properties at checkout.