There is also another issue in the demo where the error message template is configured incorrectly and always shows the "Fill in" text which might be confusing. In addition to this, there is an issue with the name of the greaterdate custom validation rule which is incorrect.
We are aware of those issues with the demo and are workign towards resolving them and uploading a new version of the demos to prevent confusion in the future. In any case, here is an updated Dojo examle where all of the above-mentioned issues are resolved:
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