Hi - I'm trying to set up wireless and external fixed IP range mapping (routed IP) re our domain (twin mail SMTP server etc) on a 2920n.

All the guides I've found refer to the earlier firmware - does anyone have a reference to well written English guidance for the 3.6.3 firmware?

TIA al

it looks like someone already helped you out with the wireless. This guide is up to date for setting up routing public IPs on to the LAN so you can assign them to your servers directly:
http://draytek.co.uk/support/kb/kb_vigor_2ndsubnet.html

Thanks - yes - Wifi is work in progress elsewhere

But the page you give is for a 2850 and that's not quite what I'm trying to achieve. At least I think it is not.

I do not want two internal IP ranges - i want to map two different external addresses from our fixed IP range to two internal ones - one for each mail server

Right okay, the 2850 has the same setup for IP routing as the 2920 does - which allows you to assign a public IP address to a device connected to the LAN and have it route through that way.

It seems you're after a setup where the router can use those public IP addresses for port forwarding and the servers would have a local IP still?
This is to set up the extra IPs:
http://www.draytek.co.uk/support/kb_vigor_multinat.html
You'd set the servers to use those IPs under NAT - DMZ Host

Then to make the servers outbound IPs the public ones you want to use rather than the main IP:
http://www.draytek.co.uk/support/kb/kb_setup_address_mapping.html