Oh- yes, you do. Sorry, I forgot about that. You will need to kill the existing powerMgr processes (I think there are more than one) before you can replace the file. Of course, once you've finished installation you should reboot the iLiad.
Re: auto-installation, I think it would be pretty easy to make an installer as with other iLiad programs, I just haven't gotten around to it. If anyone else wants to, feel free!
Besides, I figure that after opening up your iLiad and soldering a bunch of things, manual software installation must seem relatively easy.