Hi @DennyMiller ,
If You still struggling with this problem, please grab a working solution on my repo - Bitbucket
What I did - I’ve bundled (as a static resources, see - Static site generation • Docs • SvelteKit for reference) Svelte App using Svelte Kit as a Forge Custom UI component.
Routing, css and stuff - everything is working like a charm - but feel free to contact me directly in case of any problems.
Cheers,
Michal Dubel