Are you not supporting until railcraft gets put to 1.12?

only 1.12.2 is supported.

Jesus you are fast, that means you are not back porting I take it.

Do I have to fork mod tweaker then to add it in? I have been making a pack for a week, I don't want it to fail over something so simple, please provide any information you can.

Update to 1.12. I'm done with 1.10.2, and so is the community.

A fork most likely won't be accepted onto curseforge.

If you really really really want support, the only thing I can recommend is making your own addon mod for it.

I would but railcraft isn't on 1.12 yet