Nothing to do with the plugin, but having this issue with Kindle Previewer and do not know how to fix this:
Code:
E34002: Please specify the Original-resolution metadata value in the format WIDTH x HEIGHT.
This is with a fixed layout ePub, with 'positioned text'. It passes ePubCheck without errors or warnings (following 2 small edits).
Trying to convert to AZW3, either with Kindle Previewer or maybe Send to Kindle to see how it turns out. Though in the end Apple Books will be a better reading experience for these.