I enabled the PPTP service on Peplink 380 using the built in authentication. From a PC I can get a connection and log in to the remote network. So far so good.
Problem is I have no access to network resources unless I change the default firewall rule Allow All. Peplink documentation does not go into much detail regarding this so I don’t know if there is some rule that needs to be in place for the PPTP service to work.