I spent about an hour trying to figure out what this error was coming from thinking it was my geometry. So I did A piece by piece search from the small area I cordoned off that the error was in. I eventually found it was being generated by a valve prop. crane001.mdl which makes no sence to me. Here is the error -0.050800 -1.690353 0.000000 0.101600 -1.690353 0.000000 -0.101600 -1.690353 0.000000 -0.101600 -1.370356 0.000000 make_triangles:calc_triangle_representation: Cannot convert Does anyone else get this error with this model? Should I even worry about it. On another note im getting a grass mdl error also. how do I fix that. Material NATURE/BLENDGROUNDTOGRASS007 uses unknown detail object type tf_forest_grass!