Thanks for the suggestions. As I mentioned in the original post, windows services for Unix is going to be EOL soon but I found the replacement for anyone that's interested.
In Windows Server 2008 R2 you need to install the feature "Subsystem for UNIX-based applications".
Secondly, under Roles > Active Directory Domain Services you need to install "Identity Management for Unix".
Once these are installed each user will have have some extra unix attributes :)
The ldap mapping for /etc/ldap.conf is as follows:
# RFC 2307 (AD) mappings
nss_map_objectclass posixAccount user
nss_map_objectclass shadowAccount user
nss_map_attribute uid sAMAccountName
nss_map_attribute homeDirectory unixHomeDirectory
nss_map_attribute shadowLastChange pwdLastSet
nss_map_objectclass posixGroup group
nss_map_attribute uniqueMember member
The joys of interoperability...