Couple Of questions -Peering / VPN Gateway Pricing / Port Forwarding

Peering - I am trying to setup peering between two different tenants. When I go to add the peering there is a button underneath the resource ID that says "Authenticate" and when I click it a window just opens and closes instantly. Is there an easy to follow step by step on this you guys have seen that accomplish this (Using only the portal)

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VPN Gateway Pricing: If I can't get peering to work can I just setup a VPN Gateway for free? Inbound Inter-virtual network data transfers are priced as free and since it is between two azure tenants am I safe to assume it is free?

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Port Forwarding: It seems that something has changed where I am required to setup a loadbalancer to do something as simple as NAT. If I want to come in on port 5570 and have it translate to 3389 I had to setup a LB which seems like a lot of work just for something simple.