Shopify has limitations on the size of the output of carts. This means there is a limit to how many different designs Kickflip can add to the same cart.
NOTE
This limit applies to the number of distinct designs—it does not affect the quantities of the items.
How to allow more designs per cart
In order to allow more distinct designs per cart we need to reduce the number of properties per line item.
Open your product in Kickflip's product builder
Select a question
Open question settings tab (Cog icon)
Switch off show in summary
Publish and test adding multiple designs to your cart
Repeat until satisfactory
When these switches are turned off
The customer won't see the summary of those questions in their cart or at checkout.
The information won't be visible on the Shopify admin order page.
Your Kickflip order pages will always contain all of this information, regardless of the "Show in summary" settings.