With the avatar tab selected, on the right is an area called "Spring". You can try adjusting the sliders, or just uncheck spring altogether.
Also, if you go to you "Import Setting", go to default folders, there is a folder called "Avatar Setting", where you can select a couple of different "breast" settings.
The path in XP is C:/Documents & Settings/All Users/Shared Documents/Reallusion/Template/Iclone 4 Template/Iclone Template/Avatar Setting
Alley