BuildCraft version: 7.99.17
Forge version: 14.23.4.2705
Link to crash report or log:https://gist.github.com/KidEdibleGareth/898496523ec4cf1d5acaf07ef416f5b5
Singleplayer or multiplayer: Singleplayer
Steps to reproduce: Press "Play" on the Minecraft launcher
Additional information: I am playing with additional mods, but whenever I remove this one the crash at launch does not happen. This only works when removing Buildcraft, and I have tried playing with only Buildcraft as well. The mods are:

Buildcraft 7.99.17
CodeChickenLib 3.1.9.344
DimensionalDoors 3.0.9-287
DoomlikeDungeons 1.11.1
ForgeMultipart 2.4.2.60
industrialcraft-2 2.8.73-ex112
jei 4.10.0.198
journeymap 5.5.2
mellenaire 6.2.6-2
MrTJPCore 2.1.3.35
NotEnoughItems 2.4.1.233
Optifine_1.12.2_HD_U_D3
ProjectE PE1.3.0
ProjectRed 4.9.1.92-Base
ProjectRed 4.9.1.92-world
RougelikeDungeons 1.8.0

I really do expect this to be very far down the list of importance to you, due to the number of mods I have included, so do not feel rushed at all; I am but one person asking from a large mod developer.

That's odd, the crash report you've sent has a stack trace but not an exception detailing the problem...

However this looks kinda similar to other crashes with optifine, can you try changing "useSwappableSprites" to false in the "config\buildcraft\main.cfg" file?

Thank you! However, although this is likely very trivial, how would I reach that file? I've only managed to learn how to mod because I get my roommate to help me whenever I need to.
Also, I'm on MacOS.

There are two ways:

1: in game (so you'll have to temporarily remove or disable optifine to let the game launch), then go to mods > find BuildCraft > config > display> useSwappableSprites

Or

2: find the folder where your saved worlds are in, then follow the path I've already given from there.

Hey thanks a lot this solution worked!