I think a quick picture explains this, really weird, problem the best.
http://i.imgur.com/fSZOlgp.png

Other mods I have installed are SecurityCraft v1.8.2.3-hotfix, WoodConverter v2.9.2 and GlobalXP v1.2.1 (all mods that I'm working on, was testing if they work for 1.12.1).

You should post your log as well.

Yes, that would have been a good idea. Will think of that next time.
1.0.4 works, however, so I'm closing this.