Manifests with minor errors crash Tify

[dreerr]

Some of the manifests we use have minor errors in the metadata part, for example:
Validation Error: sc:Manifest['license'] must have a URI or resource, got 'Creative Commons BY-NC 4.0' (Result from Presentation Validator)
these Manifests work fine in Mirador, but in Tify they throw the error [Error] TypeError: undefined is not an object (evaluating 'this.$store.structures.length') — tify.js

Is there any way to make Tify less strict, that apart from the metadata the tiles can be displayed