And also when it is on the "OK to disconnect" screen and plugged into a USB port, is there a little charging symbol on the top of the screen? if there is it is most likely connected to the computer,and you most likely just safely removed/ejected it from your computer so then iTunes wouldnt be detecting it. If that is the case then just disconnect your iPod, reboot it for rockbox to load and then plug it in to the computer's USB port.