Our solutions are provided for free in the M365 App Store. You are free to download them and use them in your organization. You can use the samples for free provided you are not selling it or using it for commercial purposes
We created this application to show how you can leverage Adaptive Card Extensions with a visually appealing look. It is designed to show the art of the possible. You should feel free to use this app to show people what you can do with ACEs. You can get the source code here https://github.com/pnp/spfx-reference-scenarios/tree/main/samples/ace-designtemplate-gallery. If you encounter any issues please post them there.