The English patch page lists the changes between the 1.45 patch and 1.47. In addition to removing copy protection (in 1.49) so you no longer need to keep the CD in an optical drive, the bigest changes are that the Lockpick skill was fixed and the overweight penalty was changed to not being able to move (this means summoning dolls make even better mules, since they can carry unlimited weight as long as you don't need them to move around).