After updating from Zerotier 1.6.1 to 1.6.2-2 we have the following problems. The first problem is, when the line goes over the zerotier into the WAN under higher load, the traffic in the tunnel breaks down. This results in extremely long packet runtimes and packet losses. >60% . The second problem is, that seemingly UDP connections are not established properly anymore. This means that we have telephones that are connected via SIP in location A to a telephone system in location B. You can hear the ringing, but the voice is not transmitted. With version 1.6.1 everything works without problems.
regards
Christian