Cannot Get This Disk Image To Mount! I am trying to download the firmware for the RikoMagic MK802 IV, which can be found here. After it finishes downloading, I want to open it up and begin modifying it a bit for fun, but nothing I do seems to work. I've tried opening it with ext2/ext4 explorers and unpackers, I've tried mounting the disk image file in Ubuntu and Windows, I've tried using everything I could in Android Kitchen, and nothing seems to be able to get this open and editable. Any ideas what else I could try? Thanks everyone!
I picked one of those downloads at random and looked at the .img file inside the .rar archive.  It's a proprietary format.  file and trid have no idea what type it's supposed to be, the former just says "data".  The first four characters of the file are RKFW, presumably for Riko firmware.

GeekPeek.net has a pretty good guide on how to unpack and repack these files using the imgRePackerRK tool from XDA.