Patch one of your client, start it on a (own)shard with the 1.109 rollback, and fly in debug mode to NNF...
There is a lot of terrain change, that won't be fixed just with a switch in server properties
If this wasn't the main fighting (PvP) area of the game it would be just a matter of some tuning, but right now you need to move at least one keep in each realm, change some teleport if you want to go NNF PK or keep old PK's, and think carefully about mob spot for "charm" characters...
the big impact is also around the new ways opened in some area, if players use different clients they will have different clipping wall...
The bad thing about this NNF, is that it's exactly the same region as NF, so if shards want to keep player that use a live client (even with a DLL rollback) they'll have to choose whether they use the new geometry or try to rollback (patch) their player with old NF region !
It's kind of a legit "map hack", all servers still using the old NF geometry can have client with the new maps, and would be able to walk through clipping planes...