I have tried with the default of 4 segments per hair and a hair count of  5000 and tried 25 segments per hair and a hair count of 20000 - that's under  - Hair (Per Hair Group), the section underneath - Guide Hairs (Per Hair Group) is greyed out.

Even if i enable that setting it doesn't seem to want to work under Carrara 7 Pro, yet under Carrara 8 beta i can see the guide hairs move a little bit.

All the settings are default ones, thought i best mess about with the hair first then get more into the sliders later

EDIT: just did it on a vertex object and it worked, so any idea's why it wont work if i select a character?