For our guest network we use the click-through splash page. Works well for guest networks. They can just click to agree to your terms/liability. Let me know if you would like a copy of our wording to start with. You'd change the setting from Sign-On with "Meraki" to Click Through. With the current settings you'd have they'd have to have a Meraki account to login with in the browser before they'd be let online.
Adam R MS | CISSP, CISM, VCP, MCITP, CCNP, ITILv3, CMNO
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