There is one for RoR and (almost) everyone knows that it contains all the information one would need to create any new mods for the game, whether terrain or car. I'm wondering if BeamNG will have one, because I'm sure people will want to make their own cars after it is released. I know I will want to, so I can learn all about the new things that aren't in RoR like the bending rims and deflatable tires.
There used to be one but it was taken down for some reason I don't really know, therefore I'm pretty sure that there will be one.
It was taken down because it wasn't supposed to be discovered, but someone did, I just don't remember who.
I think it was bubbleawesome. I found out some pretty cool stuff in there, not gonna say it for devs sake though.
I dreamed a few nights ago that I found out the link of the download for BeamNG, but I promised the devs I wouldn't download it neither tell anyone about it.