Hey there, resident n00b speaking. I am having trouble compiling some maps. When the command is inputed to Tool.exe, it generates this error:

Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.

C:\Program Files\Microsoft Games\Halo Custom Edition>tool structure levels\mapname mapname
Couldn't read map file './toolbeta.map'
building intermediate geometry...
EAX: 0xFFFFFFFE
EBX: 0x0036C901
ECX: 0x0012F298
EDX: 0x000002CC
EDI: 0x0012F298
ESI: 0x00000000
EBP: 0x0012F170
ESP: 0x0012F160
EIP: 0x77AB70B4, C3 8D A4 24 ?????
EXCEPTION halt in .\intermediate_geometry.c,#444: triangle->material_index>=0 &&
 triangle->material_index<old_material_count 

I think this may be a materials problem. I have also observed that the BlueStreak Exporter (v1.01) creates an unnaturally small .jms file. My previous map was well over 2Mb and was, statistically, twice as small as my new map. I think this may have something to do with the textures, but I cannot be sure.

Can anybody help with this?

Either you are,
using standart materials when you should be using multimaterials, or vise versa.
have faces in the model that have no material applied to them
mave your material numbers in the wrong order.

I have been using Standard materials, but I do not understand how Multi-Materials should be named. When opening up the material browser, there are my materials, which have been given proper names to link it when compiling in Tool.

Picture: http://twitpic.com/7td5gs

Does there have to be a special name for the text highlighted? I do not know what to put if there is meant to be.

I dont use gmax, but it looks like you are doing it right.
sky has a +sky.
just add a 3rd material and you are all good.
make sure all faces in map are textured, select each id and hide the geometry, then select anything that is left and give it the correct id #.