When using the Collections > Create Monster, using the Vampirate Captain as the template, pressing Save will throw out a "403 forbidden" error. I have used other creatures as templates to create story NPC's for my maps, and haven't had this error. It seems specifically tied to the Vampirate Captain. Thought I'd throw this reply into the void in case it ever gets seen and addressed :) 

Do you own the books specifically on the account running the campaign?? Content sharing will allow for player character creation with the given species but map tokens / encounter monsters won't be enabled.

Just went into all 12 pages and didn't see this mentioned, not sure how it didn't come up sooner.

Plasmoid's species feature "Natural Resilience" has an unnecessary dropdown.

Natural Resilience

You have resistance to acid and poison damage, and you have advantage on saving throws against being poisoned.

The dropdown is just labeled "-Acid-" and only has one option "Acid". Selecting it or leaving it unselected does nothing, as you have the resistance whether it's selected or not.