all i did was look up the uses for Cobblestone and the game just crashed.

LOG

The Log should contain all important information... i mean that is the point of a crash log.

I'm not even 100% sure if this is a NC thing, it just says in the first line that it is a major bug from the mod which is adding the fluid

Yep - this was a know bug, but has been fixed in the latest version which will be out shortly :)

btw while were at it, how about the ability to use the molten materials from NC inside the casting table/casting basin from Tinkers? you knwo to make the blocks, ingots, materials etc.

I'll look into it - I imagine there's some form of IMC stuff available :)