After some 3 days of playing around, I managed to get my 7th Generation iPod working, the instructions are a bit basic, I could make a video if it helps..
1. I completely restored my ipod with itunes, stopped ihelper in the task manager.
2. Downloaded and ran https://files.freemyipod.org/~user890104/bootloader-ipodclassic-v8-designware/RockboxBootloaderInstaller_iPodClassic_v8+DesignWare.exe (BETA) to load the bootloader, I got a fail on the cannot load rockbox.ipod, when it restarted,
3. then I downloaded http://build.rockbox.org/data/rockbox-ipod6g.zip unzipped and manually copied it over to my iPod, rebooted and it worked.
hope it helps.
Does this method still work? Also, the first link doesn't work. Where would I find that?
You could build it from source, or just use of the official installer if you don't want to do that.