As far as I know the connector will work with CH modded phpBB. I don't think it shows the latest user and a few things like that though...
Now version 2.0.0 which is out to Alpha testers at the moment has some code which Martijn added that is supposed to update the phpbb_config table for the total users count, and latest username for CH...
So short answer,
V1.0.3 or before works with CH but not all stats are up to date
V2.0.0 works with all stats up to date (to my knowledge)