By "Improved Range", do you mean "Improved Critical Threat Range"? You mention a 19-20 next to it, so I'm not sure if that's the case or if you mean taking multiple stances of the "Improved Range" modification.
Assuming you meant "Improved Critical Threat Range", I don't any error (maybe the gold cost, though. Honestly, I've never used it before since base weapon prices are pretty much completely irrelevant past 1st level ).
I must note that the Crank (automatic) can be a bit too powerful, as it allows characters with low Str score to deal good damage (of course, that's kinda of the whole point of having an automated crank, but still, some GMs/players may not like it). As usual, it's up to GMs and their players to decide what modifications are allowed and how common they are.