Spline modeling is basically the same across the board for most apps, however there are some distinct differences from Carrara to 3D studio max, to lightwave but the process is basically the same. For instance. For Lightwave, you create patches for existing splines when you are manually splining. 3DS max, you use patch grids and nurbs grids which is also great but I find it tedious. Carrara already patches your splines for you in the spline room so there is no patching to it. All you are doing is making a 3D outline of the object you are trying to spline. Like if you are doing a face, then you would outline your face as though it were a 3D wireframe object. It is better shown than told so I will post an example for you.