If you want to offer free trial uses on embedded Pickaxes, you need to take a slightly different route than the Studio limits.
You’ll want to embed one version of the Pickaxe on a page that is NOT paywalled. You’ll want to set a usage limit on this embedded Pickaxe.
Then you’ll want to embed a different version of this Pickaxe that IS ON a paywalled page. This one will have no limit.