Shortly, you can only make use of this mod if you are tired of making backups of the
GTA3.IMG file. Instead of modifying GTA3.IMG, you will need to add the mods or modify
the mods in another IMG, and you don't have to worry about your original files.

If this wasn't clear enough:
You don't need to modify your GTA3.IMG to install car, skin, weapon, etc mods. A new IMG file will be used to perform this action, it's name is: overrd.img. This program will use a folder named: ovrd.

If you are using a modified gta.dat, you might have problems when using this mod.

UPDATE (v1.1):
- Now the program don't have any conflits with the gta.dat file
- Installation check button added

UPDATE (v1.2):
- Support for GTA:IV (default mod: GTA:SA Sultan)

Minor bugfix in v1.2 (2012.07.13 20:42)
- Fixed false message after succesfully patched GTA:SA

UPDATE (v1.3):
- Handling file override added
- OVRD folder have been moved in both games
- Open OVRD folder button added
- About button added
- Override status checking have been extended

Minor bugs
If you put a collision file (.col) in the overrided img you will crash the game if it exist in the original IMG. Only tested in GTA:SA but it doesn't mean that it can't happen in GTA:IV.