The demo made me want to replay the originalWhat are the mandatory mods for bugfixes and whatnot?
Ufo_extender? The AI one?
Take a look at this: http://ufopaedia.org/index.php?title=Enemy_Unknown_Extended.
Personally, I would edit the ufoextended.ini myself, but still take a look at the one they link on that page because it enables the mods and fixes the community considers safe to use, that it doesn't change the game much and provides some improvements. I do not like them all, like the aliens receiving fatal wounds, but it's a good place to start. Some will make the game a bit easier for you, and some will make it harder within reason. Check the readme for the ufoextender as well for a description of the various options, and also those that are enabled by default. If you want to deactivate one of those, you'll have to enter the line yourself in the ini file. I posted mine here if you are interested.
Code:
; UFO Extender - Mod for X-COM
; See <http://www.ufopaedia.org/index.php?title=User:Seb76> for more details.
; Copyright (C) 2008-2010 Seb76
; (updated April 2012 by Tycho/Morgan525 with thanks to Kyrub for TacticalAI mod)
;
; This file is part of UFO Extender.
;
; UFO Extender is free software: you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation, either version 3 of the License, or
; (at your option) any later version.
;
; UFO Extender is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
; GNU General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with UFO Extender. If not, see <http://www.gnu.org/licenses/>.
[Loader]
Executable=UFO Defense.exe
[Video]
Video Pitch=0
HQ4x=0
D3D=1
D3D Windowed=0
Always On Top=0
Clip Cursor=0
Scale Mouse=1
Screen Ratio=1.111111111111111
Max FPS=60
CPU Mask=0
High Priority=0
Force Language=1
Skip Intro=1
D3D Window Position=0 0 480 600
[Mod]
Alien Inventory=0
Alien Bleeding=0
More Reaction Fire=0
Hot Grenades=0
Stunned units KIA=1
No Blaster Bomb Drift=0
More Smoke=1
Heavy Laser=0
Stun Fest=1
No Auto Wake Up=0
No Alien Freak Out Messages=0
Auto Sell=1
Start With All Missiles=0
Assign All Personnel=1
General Store Capacity=0
Rank In Inventory=1
Show Money=1
Base Building Stacking=1
Fast Base Defenses=0
UFO Responds to Interception=0
Difficulty Level of Interceptions=0
Manual Interception Fire Mode=0
True Cautious Mode=1
Crafts Always Ready=0
Retaliate Against Ground Assault=1
No Funkers=0
Bloodthirst=0
Disable Base Defenses=0
Surrender Defence Missions=0
Initial Alien Bases=0
Funding Council Income Only=0
Limited Military=0
[Enhanced Tactical AI]
Apply=1
Autofire Distance=8
Snap Distance=16
[Equipment Screen]
Show Grenade State=1
Primed=primed
Save Equipment=0
Auto Flares=0
Show Stats=1
Weight=Weight>
Accuracy=Accur>
Reaction=React>
Psi Strength=P.Str>
Psi Skill=P.Skill>
[Bug Fix]
Tactical Scroll=0
Animations Speed=1
Intro Sounds=1
Music Change Freeze=0
[Range Based Accuracy]
Apply=1
Minimum Efficiency=50
Snap Penalty Distance=30
Auto Penalty Distance=14
Orange Cursor Threshold=95
Red Cursor Threshold=75
[Line Of Fire Check]
Mind Control=0
Panic=0
Mind Probe=0
[Music]
Apply=1
Source=MP3
;Source=PSX CD
CD Drive=F
MP3 Folder=mp3
Battlescape=*Battlescape*.mp3
Start Menu=*Final Briefing*.mp3
Bad Ending=*Final Briefing*.mp3
Good Ending=*Dogfight*.mp3
Geoscape=*Geoscape*.mp3
Dogfight=*Dogfight*.mp3
Mission Debriefing=*Debriefing*.mp3
UFO Assault=*Briefing1.mp3
Base Defense=*Briefing2.mp3
Base Attack=*Briefing1.mp3
Mars=*Debriefing*.mp3
Terror Mission=*Briefing2.mp3
[Initial Base]
Apply=1
row1=HangarTL HangarTR HangarTL HangarTR HangarTL HangarTR
row2=HangarBL HangarBR HangarBL HangarBR HangarBL HangarBR
row3=AccessLift Empty Empty Empty Empty Empty
row4=GeneralStores LivingQuarters SmallRadar Laboratory Workshop Empty
row5=Empty Empty Empty Empty Empty Empty
row6=Empty Empty Empty Empty Empty Empty
[Battlescape Shortcuts]
Apply=0
End Turn=Return
Multilevel View=
Show Map=
Center On Unit=
Inventory=Space
Kneel=
Next Unit=Tab
Next Unit Skip Current=Back
View Up=Prior
View Down=Next
Go Up=Up
Go Down=Down
Left Menu=Left
Right Menu=Right
Unit Stats=
Options=Escape
Lift Off=
Reserve None=1
Reserve Snap=2
Reserve Auto=3
Reserve Aimed=4
[Geoscape Shortcuts]
Apply=0
Rotate Right=Right
Rotate Left=Left
Rotate Up=Up
Rotate Down=Down
Zoom In=MouseWheelUp
Zoom Out=MouseWheelDown
Geo Speed1=1
Geo Speed2=2
Geo Speed3=3
Geo Speed4=4
Geo Speed5=5
Geo Speed6=6
Intercept=MouseMiddle
Bases=B
Graphs=G
Ufopaedia=U
Options=Escape
Fundings=F
[Caps]
Apply=0
Time Units=80
Health=60
Strength=70
Energy=100
Reactions=100
Firing Accuracy=120
Melee Accuracy=120
Throwing Accuracy=120
Psi Skill=100
[Wreck Analysis]
Apply=1
Zone Discovered=Intel found out that the %s UFO was raiding %s
Mission Discovered=Inspection showed that the %s UFO was on an %s mission
Both Discovered=Ship investigation revealed that the %s UFO was on an %s mission in %s
[Craft Ready Message]
Apply=1
Title=Aircraft ready
Info=A craft has been refitted
[Roswell]
Apply=0
;Terrain names
Jungle=Jungle
Farm=Farm
Mountain=Mountain
Desert=Desert
Polar=Polar
;Dialog strings
Title=UFO Incident
Info=Crash reported
Location=LOCATION
Type=TYPE
Terrain=TERRAIN
[Hack]
No Score Game Over=0
Big Brother=0
Alien Pets=0
No Alien Psi=0
Directly Use Alien Weapons=0
Recover All Clips=0
Show All Locations=0
FPS=0
[OBDATA.DAT]
Apply=1
;Make grenades indestructible to allow stacking several explosions
Grenade Resistance=255
;Make HE packs capable of breaching UFO walls
High Explosive Damage=200
Heavy Plasma Weight=10
Pay also attention to the Screen Ratio section. X-COM uses a 16:10 ratio (originally 320x200), so if you have a 16:10 screen, simply use a value of 1 to have the correct aspect ratio in fullscreen. If you use a 16:9 screen, like I do, then use 1.1111 to correct it.
The latest version of the UFO Extender have the kyrub AI patch, unless you mean another one.