Problem with Vatican Library manifest

[robcast]

I am trying to display Vat.ar.319 (https://digi.vatlib.it/iiif/MSS_Vat.ar.319/manifest.json) using Diva.js and I'm only getting an empty Diva frame. There seem to be two problems:

I get an error about page 0:

Uncaught (in promise) Error: invalid page: 0
    at Renderer.load (renderer.js?baad:70)
    at ViewerCore.reloadViewer (viewer-core.js?663e:404)
    at ViewerCore.setManifest (viewer-core.js?663e:1166)
    at Diva._loadObjectData (diva.js?f00f:243)
    at eval (diva.js?f00f:176)

It works when I start Diva with a goDirectlyTo: 7 setting.

Then I get lots of CORS errors:

Access to image at 'https://digi.vatlib.it/iiifimage/MSS_Vat.ar.319/Vat.ar.319_0008_fa_0001v.jp2/0,0,512,512/256,256/0/default.jpg' from origin 'http://localhost:9001' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

It works when I disable CORS on the images with the imageCrossOrigin: null setting.

So there seems to be a problem in processing the manifest and also maybe crossOrigin=null should be the default.

[robcast]

In the manifest the first seven canvases in sequences.canvases have viewingHint: non-paged.

It seems that the default setting of showNonPagedPages leads to the first pages being ignored in ImageManifest which may be intended but Diva still uses the default start page of 0 which leads to the error.

It works then I add the setting showNonPagedPages: true.

A better fix would be if the logic for calculating the start page would take the ignored pages into account.