I never played the DOS version. I started with the collectors edition. =) But it was always rather funny, when the soldier turned to its supposed victim but didn't do anything, as there was an obstacle, or he just turned short of 1 TU to fire. But I only learned here, that this meant a successful reaction roll and thus counts as one for the increase of reaction skill. I always assumed, that a non successful try to react wasn't counted. But there's a certain logic behind that counting it anyways.