Looked for the lava texture for a while now but can't seem to find it.
try these
imp_mine/lava2.jpg (lava tile)
common/lav1 (rocky lava tile)
koribban/k_floorlava (lava edge)
there are a few others but i cant seem to find 'em, ill reply later when i do though
:)
*edit*
aha, in desert/, a bunch of misc ones m1 to m8.jpg