Did some digging around, came across this:
UK and US versions.
Carmageddon 2 has a version of SafeDisk copy-protection that requires it to be running on a Windows 9X operating system.
A generic EXE unrapper called 'UnSafeDisk' can extract the real EXE from the ICD file, and this file has no issues running under XP.
Do a google search for "GameFix" and try downloading UnSafeDisk from the "GameFix" website.
More info from "MP3Vampire":
1. Keep a backup of the old exe, i.e. "CARMA2_HW.EXE.BAK"
2. Rename one of the files generated by UnSafeDisk to be "CARMA2_HW.EXE", if you try to run the files directly you wil get errors, cause commands have to be sent to the file to run from "carma2.exe", the working file usually produces an error message "BRender error detected: Failure: Could not reference image glide2x" this is because by default they have tryed to run the program on 3DFX cards.
3. Once you know it is working you can delete the extra file