To add custom designs to your presentation, you must first save the presentaiton to disk. Then, inside the folder with the markdown files, create a folder called designs.
Drop your custom designs (e.g. the example designs) into this designs folder. Your folder structure should then look like this:
[parent folder]
+--- [presentation name].md
\--- designs
\--- example
+--- simple
+--- dragonfly-light.jpg
+--- dragonfly.jpg
+--- design.css
+--- design.json
\--- preview.md
Once you have done this, you can select the example designs from your marmota.app presentation:
When selecting the designs works, learn how to create your own desings