I just had Microsoft logged on to my server and investigating as I was almost sure that the problem must be with RRAS server or Hyper-V setup but they brought very interesting point. Theylogged on to remote computer and tried 'telnet xxx.142.86.45 1723' and the port appears closed. I then tried telnetting to two of my other clients networks who has the same srx100 firewall with teh same policies and it worked - I was able to telnet on port 1723 for these two clients.
Microsoft then installed some 3rd party port monitoring tool on my host server and they were able to telnet to my RRAS server. All of these test are evidence that the problem is on the srx rather then anywhere else.
This also means that 'ransmission hits and successfull session values don't mean that traffic is getting through but this means that it is only 'hitting' srx.
Answering pantunes question - there is nothing in logs on the RRAS server whenen trying to accces from the Internet. Events are only being logged when establishing vpn connections locally from LAN clients.
So the problem is with NAT destination rules or Policies on srx. Anyone?