One question though. I skimmed through the thread a bit and there was some mention of new magma safe rocks. Is there a more in depth readme (read the one in the first post) somewhere that contains this info and other tweaks from vanilla? Or if someone knows could they tell me? I'd like to get my metal industry started to outfit my army asap.
You could try the list from my
Molten Rocks mod, as that's where DD got the magma-safe stones from. I'm not sure what version of MR is used in DD though, so there may be a few stones that are safe in MR, but not yet in DD.
I think all versions of MR had alunite as magma-safe, though. Since you have magma, you probably have an igneous extrusive layer, and those are loaded with alunite. I'd give that a shot.

If I recall correctly, dolomite was also an early entry, and it comes in entire layers, so if you have it, you'll be swimming in magma-safe stone. Quartzite and chert also come in layers, but I think those were relatively late additions. If you have them, you could try dumping a stone in the magma to see if it melts or not.