i had difficulties transferring null_.zip also but figured it out
i just got my $99 galaxy gear and played with it for a bit. first of all, i wasn't sure how to initially program it without a samsung phone, but eventually i just used my son's g4 to initially set it up. then i did the quick cydia impactor
root method. i installed gear manager and all its associated files on my lg optimus g pro in order to pair the gear with a NON-galaxy device
. i used odin to install twrp recovery via these instructions
. and i tried to install null rom according to http://nullproject.net/guide/
and download site. BUT I HAD PROBLEMS attempting to transfer the null rom zip file to the watch. it took me a long time to figure out how to move the files to the watch and my laptop wouldn't connect (windows 8) to ADB PUSH the rom over. after a while, i figured that i could boot into twrp recovery, MOUNT SYSTEM, and THEN MY COMPUTER could transfer the null rom to sdcard via: adb push null_23.zip /sdcard
after that, it was gravy and i had success installing null 23 rom onto my galaxy gear! i hope this helps...