I did it from cold.... I did mean to heat the water up first but didn't realise you needed to set a time to do so - it kept shutting off the temperature. DOH!! But I know now. (Like I also know now that the kneading button doesn't work if you set it to anything greater than ) - another time that I was convinced I'd broken my machine!)
Re the water - I haven't really measured it and I'm not aware of a particular formual/table thermomixer but HO might have something?