No, in my opinion anyway curvature calculations are not very straightforward as one would think, as there are discretization and numerical effects that can really mess with the numbers. As I'm sure Dan Patterson will soon point out, you can always write your own focal functions using bumpy arrays if you have a particular flavor of calculation you want to do.
I think it's great you found some other software that seems to do what you want. As for moving the results back to ArcGIS, raster data conversions can be tricky if the header file for the .bil is not exactly right for ArcGIS to properly interpret the data. I suggest messing with the .hdr file options you have been using, consulting this help doc:
Sorry to resurrect this thread, I see now it's an old one. More discussion from similar old history here: