I'm trying to make [Murus](https://murusfirewall.com/) block everything, except my connection to the VPN server. I don't want my Mac to make any outbound calls to any ports unless via the VPN connection. I'm trying to add a rule that allows the VPN, while everything else is blocked by `set block-policy drop`. I can connect to the VPN, but nothing works aside from that. Can you point me to the right direction?