When I run yarn run export / npm run export, only one of my routes get exported as a separate static html file. I want all of them to get exported, into their own .html files.
Am I missing a setting?
The only route exporting is /login
You can check this in this repo (i cannot provide samples, since I don't know what causes this issue): https://github.com/useverto/verto
When sapper export is run you'll see that it first builds the app, runs it, and then crawls the links it finds to determine the routes it can export.
https://sapper.svelte.dev/docs#How_it_works
Because the Nav component in your app only exposes / and /login as links when loggedIn is false, the export will only see and follow those links. The /trade and /gallery links in your app are only rendered once loggedIn is true, so they'll not be seen by the export.
You can add other routes to be exported with the --entry option to the sapper export command. So in your case you could change the export command in package.json to something like...
"export": "sapper export --legacy --entry '/ trade gallery'",