As for the OP . . . there is a LINE6 WiKia for the HELIX here: www.Line6.WIKIA.com. It is not "complete" but there is a lot of good info and it continues to get better as the community adds info.
There is another address which links the Amps, Effects, Cabs and Mics to the original manufacturer's User Manuals but I can't seem to recall that one. I'll do a lttle research and EDIT HERE if I do locate it.
See MisicLaw's post below for the other LINKS. Thanks MusicLaw! Bo