On reboot the default transmission-daemon does not automatically resume torrents. They start as "paused" or "finished" or sometimes they even start re-downloading again (weird bug that I haven't troubleshooted yet).
The fix for this is to change the start priority in /etc/init.d/transmission to 98 instead of 99. Then the torrents resume their previous state successfully.
Is this a bug with OpenWrt or Transmission? Is there any problem with setting 98?