[MarioL]

I'm sorry but some of the IPs you put there are confusing me a bit. So I'm just going to give you a generic answer. Also, ideally you shouldn't NAT directly to LAN, servers that need direct inbound access from the Internet should be on a DMZ.

If you have a /30 subnet, if you use the BC address for NAT you will have problems. There is a reason why the BC address exists. An exception is if that network isn't being used, but rather routed to the firewall for NAT purposes specifically in which case you could use all 4 addresses, including the Network one.

If I was you, I'd just create manual NAT, using the firewall address as the public address for the internal server, for specific ports.

Example:
You have an internal Web server that needs to be access on port 80.

Create 2 objects for the server, one with the internal IP and another with the firewall's external IP.

Create 2 manual NAT rules as:
Any | FW IP | http --> = | Server IP | =
Server IP | any | any --> FW IP hide | = | =

That should do it. It also allows the server to go out to the Internet hiding on the FWs IP. If you already have a Hide for the LAN, the 2nd rule might not be needed.

Hope that helps.