IPsec in 6.47beta60 seems to be broken, multiple users report this - http://forum.mikrotik.com/t/v6-47beta-testing-is-released/135326/1
In your log in particular, I can see the IPsec stack has received a packet from the remote peer but didn’t bother to parse it.
What feature in 6.47beta60 is so important for you that you’ve chosen it?
Did the previous Zyxel work against this ROS version or some other one?