ddwrt router set up pptp server but won't connect?

Question

VPN

Set it up like this. Connect. from the laptop which is sublingual to this router. but doesn't work.
I want to connect to the Mikrotik groove router, which is at home behind two NATs. But now it doesn't work like this. Although the Internet is.
How to make it so that there is a connection from a laptop, and then from a remote mikrotik.

Answer 1

1. Server IP - NOT the external IP of the router, but an unoccupied address from the local network range NOT falling into the range issued by the router via DHCP and NOT the router's LAN address.
2.Add to Administration->Commands
iptables -A INPUT -p gre -j ACCEPT
iptables -A INPUT -p tcp -m tcp --dport 1723 -j ACCEPT
Click Save Firewall.
3.Reload the router.
Official Wiki
For Windows 8\8.1 clients, select Microsoft CHAP v.2 in connection settings-security

Answer 2

Check the availability of ports 1723 and 47 on the router