How do I build custom components in 3.148?

I'm following the documentation but am encountering problems at npx retool-ccl dev. This fails with a 400 (Bad Request). Checking logs on my instance, I see:

Invalid path retool-custom-component-manifest.json.js in zip file. Path cannot be an absolute path, cannot contain the character | and must be one of the files [components.js, components.css, retool-custom-component-manifest.json]

I'm using the template repo (GitHub - tryretool/custom-component-collection-template) with no changes. A file called retool-custom-component-manifest.json is created in the root of the project when I run the dev command.

I'm not sure what zip file it's talking about. Can anyone help?

Reported on github: Unable to upload components on 1.6 ยท Issue #13 ยท tryretool/custom-component-collection-template ยท GitHub

This was fixed in 1.7 (see GitHub issue).