Hi,
I have XO CE (built from sources on a 09/24 commit) and I use the LDAP plugin connected to a Samba4 AD controller running on Debian. I'm not sure how different it is from a real Windows AD DC.

My config is working and looks like this :

URI : ldap://IPv4:389
check certificate : no
use starttls : yes 
Base : OU=MyOU,DC=company,DC=tld

DN :
username : CN=serviceaccount,OU=MyOU,DC=company,DC=tld
password : the service account password

user filter : (&(cn={{name}}) memberOf=CN=ADMIN_AD_GROUP,OU=Groups,DC=company,DC=tld)) 
ID attribute : cn