When opening the spellforger's codex an error message appears behind it saying "that book didn't load correctly..." this persists with server, and client restarts and creating new books as well. Additionally when making spells, no matter what is chosen or how many are made only one entry ever appears in the codex, with the only ingredient being a nacre pearl.
Here's an image of the nacre pearl spell structure:

And a couple of pictures showing the book error:

2018-08-20-4.log.gz
latest.log

I hope this is informative for you. If there's anything else you need please let me know.

Could you give us the log from when this happened?

The logs you gave us are from previous instances.

I'm sorry for the late response, i've been busy with work for the last couple weeks. I can't figure out which log shows the earliers instance, i've added the logs to a zip file to upload here.
logs.zip

Going back and reading when I'm a bit more awake, you wanted the logs from 08/21, right?
It made 6 of them,
2018-08-21-3.log.gz
2018-08-21-4.log.gz
2018-08-21-5.log.gz
2018-08-21-6.log.gz
2018-08-21-1.log.gz
2018-08-21-2.log.gz

I've attached all of them to this post.
Some additional information:
I've taken the troubleshooting steps of making sure all mods related to wizardry are up to date. That didn't help.
Updated all the other mods in my modpack. That didn't help.
Checked that all my drivers are up to date. That didn't help either.
Java is running on java 8 update 181.

I also read through some of the log files, and couldn't see any obvious errors in it, but i'm not super experienced with checking for stuff like that, so I may have missed something.
Attempting to delete, and reinstall wizardry and related mods also didn't help.
Tried to make a spell in single player, hoping that the error might be server side, but that didn't help either.
I'm guessing Wizardry, Forgelin, or LibrarianLib are conflicting with something, but i'm not sure what they could be conflicting with.

And the last thing I can think of, it's Shadofacts forgelin, right? That was the only one I could find when I went to download one.

Here's a lit of all the mods.
mod list.txt

Update: Spells load but the message appears on servers wtihout reason

After the next update we're dropping support for 1.12 outside of major issues.