Update some base materials with correct surfaceprops Mostly affects HL2 coast maps, so footsteps/impact effects are correct Episode 2 material surfprop fixes Fixed a crash when reloading textures CSS map material surface prop fixes Improve how death is handled when NPC is killed by a harpoon Other game systems can now detect these deaths, such as the Antlion Guard section on d2_coast_11 (OnDeath output runs, etc) Added LuaMesh.__tostring Throw a non halting error when GetRenderMesh has a mesh. but not a mat Prevent a crashing issue with multicore and IMesh:BuildFromTriangles