Hello,
im not sure, if i had same problem or something little bit different, when i started play cod.. But i fixed it thnx this:
(Sorry for my very bad english.)
For 1.0 version u must delete "iw_15.wid" in activison/cod2/main and put different "localized_english_iw11.iwd". This file is different for 1.0 and 1.3, but have same name. But different size (for 1.0 its 126kB and for 1.3 its 1kB). So i copy this file from version 1.0 on desktop and when i wanna switch from 1.3 to 1.0, just copy it to cod2 folder, delete iw_15 and put crack, couse i have cracked version. And its working and i can quickly switch to versions.
And if u wanna this file for 1.0, i uploaded it here:
http://www.filedropper.com/localizedenglishiw11I wish, it help!
Have a nice day