[cvsnt] access permission problem

[Shepherd]

I built a server months before using 2000 file permission to control access,
worked well.
Recently I built a new server, checked all three boxes in 'advanced' of
control panel, but NT file permissions do not work: only administrators were
assigned permissions to cvsroot, but any users had full access permission to
it.The config file is default ,"SystemAuth=no". So I set acl using 'group'
file, but it did not work well: some users were in several groups, but he
could not access all the projects which were assigned permissions to him by
group. I am using build 66.
Why windows2000's file permission does not work any more?
What's wrong with my settings of acl?

Shepherd