Remoteapp through a standard NATing firewal

i'm attempting setup simple remoteapp environment client needs remote access program. here's have:

1. server 2012 standard active directory dc (server12)

  - has program installed on there

  - rd session host

  - rd gateway

  - has rd web access

  - has rd licensing

2. virtual hyper-v server 2012 standard connection broker (rdbroker)

if i'm in building on intranet, or connected vpn, can access perfectly. however, remoteapp rdc connections looking connect rdbroker, instead of rd gateway. there way fix this?

-nate

for remote apps work via rdweb site need port 443 , port 3389 forwarded rds server, because works internally or via vpn sounds firewall need configured properly. 

some people saying 3389 not required if not forwarded , doen't work solution.

Windows Server  >  Remote Desktop Services (Terminal Services)