Running L2TP\IPsec aside IPsec tunnel

Hello,
I’m facing problem with L2TP\IPsec. I have two IPsec tunnels and I want to run L2TP\IPsec VPN server for users to connect. I putted network scheme bellow

I have tried many tutorials, including this http://wiki.mikrotik.com/wiki/Manual:Interface/L2TP#L2TP.2FIpSec_setup alse youtube tutorials.

In http://wiki.mikrotik.com/wiki/Manual:Interface/L2TP#L2TP.2FIpSec_setup tutorial note says that some care must be taken. I don;t know hat care is needed. Can someone tell me more what is needed?

Which part of your setup is working? Which part isn’t working?