Anyway the function sim.can_move can be used to make particles move through gasses. Something like sim.can_move(tpt.el.dust.id, tpt.el.gas.id, 2) would make dust move through gas
What jacob1 posted is a Lua command and as such can be run directly from the console (watch out for the order of parameters though). And yep, it's Lua, not LUA.