NAT Setup:
If Proto Ext. port range NAT IP Int. port range Description
WAN TCP 80 (HTTP) 192.168.2.7 80 (HTTP) Internal Web Server
Rules Setup:
TCP * * 192.168.2.7 80 (HTTP) NAT Internal Web Server
I just set this up and tested it out. Seems to work fine for me. Make sure in your Firewall: Rules that you have Source and Port set to "Any" (*) from external.
Hope this helps.
Michael