Set no. of galleries/page in pro grid album

I am creating a pro grid album which will ultimately have some 100 or so galleries, obviously too many to be viewed on one page. I’d like to set the number of items per page to (say) 12 galleries, but I don’t see the “Items per page” setting in the pro grid album “Customize display settings” menu…

The option is however available in the Basic compact album menu…

Is this intentional and if so, is there some way round the problem? I have tried simply adding galleries_per_page=”12″ to the Pro grid album shortcode, but it has no effect.

Thanks for your guidance.

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