This mod prevents clients from joining the server with "Incompatible client! Please use Neoforge X.XX.X" message. Updating version doesnt help, however removing the mod from server fixes it.
Tried on both offline + cracked and online + mojang logins, doesnt change anything.
Disabling FML update check on client also didnt help.

Mod version - 0.6.16c

Logs (on online mode and license account, the only mod is CPM):
logs-cl.zip
logs-sv.zip