It requires a paid license for full functionality after a 30-day trial period. There are no legitimate "free license keys" available — any website or video offering such keys is almost certainly distributing pirated software, which carries risks including malware, keyloggers, account theft, or legal consequences.
I understand you're looking for information about ZModeler 3 license keys, but I should clarify a few important points first. zmodeler 3 license key free