Lightroom Classic fails to upload book to Blurb

[nzphotomike]

Hi community

Has anyone come across the issue when uploading a book from Lightroom Classic  to blurb where it immediately fails when trying to upload? It goes through all of the 'rendering pages' steps, but fails immediately when it starts to upload the cover. It produces a very generic programming language error:

An internal error has occurred

?:0:  attempt to perform arithmetic on filed 'chunk_size' (a nil value)

I've seen 'workarounds' exporting to PDF and then sending to Blurb, but it's not really a workaround but rather simply not using the integrated upload feature. Uploading the PDF to Blurb seems to work okay, even if it does complain that the page size is slightly different (which it is able to auto-correct during the web upload process)

Lightroom version: 11.4.1

Mac OS: Big Sur 11.6.8

Thanks

Michael

[TheDigitalDog]

Appears to be some kind of Lua error from what I can find. 

Try resetting your Lightroom preferences, can't hurt:
https://helpx.adobe.com/lightroom-classic/help/setting-preferences-lightroom.html
Also see: https://community.adobe.com/t5/lightroom-classic-discussions/important-steps-for-manually-resetting-...

Quit Lightroom Classic.
MacOS: Press and hold the Shift + Option keys.
Windows: Press and hold the Shift + Alt keys.
While holding down the keys, launch Lightroom Classic.
When asked, select "Yes". 

If that doesn't work, maybe try uninstalling LR using Adobe Creative Cloud, and then use it to reinstall LR.