I am using the terminal and I have tried ADB as well. Both do the exact same thing. I obtained root manually but I had so many problems that don't remember where the guide that I followed is. I named the recovery image "r.img" for ease of typing.
I don't know about rom,kernel,baseband/radio, and hboot. I flashed stock to the phone after purchasing it so that I could get it activated, so these things are likely at defaults.
I still don't think that the "flash_image: not found" error has anything to do with the image file itself.