[1.7.10]Can't test run mod with other mods

[iWasHere]

Using the latest version of Forge for 1.7.10 [10.13.3.1408].

I'm trying to make a mod that uses the redstoneflux api, but I want to be able to use Thermal Dynamics + Expansion with it for ease of testing, but putting the mods into eclipse/mods will crash the game. I tried this with many other mods like CodeChickenCore+NEI (the loader crashes at startup) and even Botania (which won't crash, but when I add Baubles it crashes). I'm not sure what to do, and considering I was able to get this to work in an earlier version of Forge [10.13.2.1291], I have no clue what I'm doing wrong.

 

I tried to downgrade forge using the build.gradle file, but it didn't work, so I'm basically stuck until I can fix this.

 

Thanks in advance.

 

EDIT: totally reinstalled forge, tried adding the mods to be used in-game, same error.

[UnnamedProdigy]

It would really help if you post a crash log.