Problem with sep firewall and dameware mini remote access

I have a problem between sep firewall and dameware mini remote.

I've allowed port 6129 in the firewall and when I try to remote to the pc it waits at authenticating for around two or three minutes before I can get a remote desktop. So something else is not working correctly.

If I disable firewall everything working fine. No delay when remoting in. The remote pc is a special purpose machine which only have sep firewall on it no other components. Only certain traffic will be allowed and all else is denied. It is unmanaged obviously.