The software is cumbersome and has a steep
learning curve.
I would call it more of a learning PLATEAU than a curve. I stared at this thing off and on for about a week, hopelessly lost. Then suddenly, it finally clicked for me about how the structure and programming for the ProntoNG worked. (And before you ask, OF COURSE I didn't read the manual. I'm an engineer, after all!)
Once I determined what I wanted, it took me about four solid hours to set up a basic configuration I liked. Since then, I tinker with the software on my laptop during commercials, modifying the interface and adding little functions and macros.
I now consider tinkering with the ProntoNP a new mini-hobby. (I guess based on the ProntoPro contest results, I'm not alone in this hobby!) Also, my wife very much likes the simplicity of the graphical interface and the reduction from six remotes to just one.