Yes the dealer needs to purchase the licence from Houselogix for usage over the 48 hour trial limit. They will need to sign up for an account. It may take Houselogix a day or so to verify that your dealer is an authorised Control4 dealer prior to authorization. In the meantime the driver can be downloaded without a login for evaluation using the trial licence.
If you utilise the trial and it expired then your dealer can log in remotely to your system after 2 days to add in the purchased licence key should you decide to proceed.