Issues between Windows Server 2008R2 and XP x64

I am having issues with profiles and group policies between my Windows
Server 2008 R2 x64 and Windows XP x64 SP2 client machines. This is a
small closed internal network that must use XP x64 as a client and
would prefer to use Win2k8R2 as the server. The domain has been
successfully setup and active directory installed. There are four user
groups, approx 20 users and 10 workstations (5 XP x64 SP2 and 5 XP x32
SP3) and 2 additional Win2k8R2 servers.

What are the proper steps I need to take to enable the XP machines to
receive group policies from the Win2k8R2 server?

What steps need to be taken to allow for roaming profiles down to the
XP clients?

I read something about Client Side Extensions but when I try to
install them for the XP x64 SP2 clients the installer says package is
not necessary based on the service pack.

Thanks!