I’m sure if it wasn’t for this the Beta version wouldn’t be available to be honest. There are several other new features in it that are still a bit buggy.
I have not used this yet, so I’ve been looking at the code. It appears that Elliot has set this up to work on a filter, at least for now. I don’t see a place in ACF where you can enter the values and maybe he plans to add this later. At any rate, here is the relevant code from ACF
It appears that you’ll need to create a filter in functions.php to set up the api key.
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