Here is an example of what is generated in the text
file after one connection attempt.  The username in
this case is "radius", the IAS server is "Zircon",
the IAS ip is "192.168.1.11", the M0n0wall IP is
"192.168.1.3", "Monowallx" is the name of the radius
client:

192.168.1.3,radius,10/09/2004,21:23:38,IAS,ZIRCON,6,1,32,m0n0wall.ogden,5,0,61,15,4108,192.168.1.3,4116,0,4128,M0n0wallx,25,311
1 192.168.1.11 10/09/2004 21:09:56 41,4136,1,4142,0
192.168.1.3,radius,10/09/2004,21:23:38,IAS,ZIRCON,25,311 1 192.168.1.11 10/09/2004 21:09:56
41,4128,M0n0wallx,4116,0,4108,192.168.1.3,4136,3,4142,49


In my remote access policy I have in the conditions
to check that it matches an Active Directory group
which contains a user who has dialin enabled.  There
is also a condition, generated during the creation
of this policy as directed by the guide you linked
earlier, "NAS port type matches VPN".  From other 
posts i've gathered that this line should be removed
because M0n0wall captive portal does not return a NAS
type.

Thanks for your quick responses and suggestions
Chris.

-Peter