The IAD-200 / IAD-200W processes the data passing through it, so it is not transparent. For incoming connections, you must use the Virtual Server or Firewall Rules to specify the PC which will receive the incoming traffic. You can also use the DMZ function. This should work with almost every application, but:
*It is a security risk, since the firewall is disabled.
*Only one PC can use this feature.
[Note: Can also apply to other router]