Ok - I've followed the aforementioned tutorial precisely up to step 4. When I try to boot the kindle up, it shows orange logo, then blue logo, then looks like it's trying to boot normally, then sends me into TWRP.
Is this what is called "boot loop"?
At this point my PC doesn't see the sdcard so I can't get CM/Gapp copied over.
Would it be safe to push CM & Gapp to the sdcard using adb, then resume with TWRP?
EDIT: Still can't boot into the system. Just sideloaded CM 10.1 ROM onto the sdcard. Safe to continue with Step 4, wipe stuff, and install the CM rom?