Make sure you have these settings in IGC_Common.ini:
Code:
MainExeCRC = 0 ; main.exe
DLLCRC = 0 ; IGC.dll
PlayerBmdCRC = 0 ; Player.bmnd
SkillCRC = 0 ; \Data\Local\Eng\Skill_eng.bmd (only)
DisconnectOnInvalidDLLVersion = 0
There's a possibility that the GameServer is bypassing this because it could actually have hardcoded values inside for these checks and not taking them from IGC_Common config.
I recommend to recompile the GameServer_Regular and eventually debug it from VS, breakpointing, etc.
If these are not working, then the initial GS_Normal and source codes (if you recompiled the GS_Normal) are bugged.
IGCN server files repacks are not completed and they're pretty buggy, so you would eventually need to fix the bugs by yourself using these source codes.
These files are pretty good for learning purposes, but not for a live server. For an online server there's many things to be fixed, and there's a possibility that the source codes are incompleted (IGC.dll and GameServers).
Another possible thing you can try is add the CRC for each one. You must use Mu Toolkit. Open it -> Client Tools -> Compute MU CRC for your files and DisconnectOnInvalidDLLVersion = 1.