Trying to get piratebox running on the Unwired One (formerly Black Swift)

I posted about the Black Swift quite a while ago (probably years ago) and mine has finally arrived. For those who are unaware, the Unwired One (as the Black Swift is now called) is a tiny (barely bigger than some coins) single board computer that runs OpenWRT. It has wifi on board by default, a USB port for power, and a USB port for whatever else.

I've been trying to manually install PB on it for a few hours and I keep getting stuck at:

/etc/init.d/ext init

It seems like it's going fine, but then it'll just hang at "Starting" and never go farther. After additional investigation, it looks like mounting the img might be the sticking point. Running this manually:

mount -o loop,rw,sync OpenWRT.img /mnt/ext

results in it just hanging. There are never any errors, it just doesn't seem to be doing anything.

Any suggestions would be appreciated.