By the looks of it your mod is using the default minecraft prefix and spams the following into the server logfile.
Potentially Dangerous alternative prefix minecraft for name cfmoven, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmfridge, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmcabinet, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmfreezer, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmbedsidecabinet, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmmailbox, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmcomputer, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmprinter, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmstereo, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmpresent, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmbin, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmwallcabinet, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmbath, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmshowerhead, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmplate, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmcouch, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmtoaster, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmchoppingboard, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmblender, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmmicrowave, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmwashingmachine, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmdishwasher, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmcabinetkitchen, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmcup, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmcookiejar, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmtree, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmmirror, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmgrill, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmeski, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmdoormat, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmcrate, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmlightswitch, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmceilingfan, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmdeskcabinet, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmmodernslidingdoor, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmdigitalclock, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmtv, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmkitchencounter, expected cfm. This could be a intended override, but in most cases indicates a broken mod.
[19:34:32] [Server thread/WARN] [FML]: Potentially Dangerous alternative prefix minecraft for name cfmkitchencounterdrawer, expected cfm. This could be a intended override, but in most cases indicates a broken mod.

Crash report
Does not cause a crash but certainly is concerning when you read it and tagging it correctly now will save me having to go and edit the world files which I don't really want to do.

To Reproduce
Install Forge, install mod, run game.

Screenshots
Not really necessary.

Please complete the following information:

• Minecraft Version: 1.12.2
• Mod Version: cfm-5.7.0-mc1.12.2

I would appreciate if you don't want to fix this because it could damage existing worlds if you could tell me what to change so I can fork it, change it and won't have to edit it in the future.

Cheers in advance. forgot to mention I can go back to a previous saved world file before the mod was applied to check for clean install as well.

I unfortunately can't change this. This is to do with Tile Entities. If I was to change the id, all existing tile entities from my mod would lose all their data. I will be fixing it once 1.13 Forge comes out.

Any possibility you could explain to me how to do it and I could fork it for my own use? I'm trying to set things up with the hope of porting the world to 1.13.x without edits.