The heroes cannot attack or move while sleeping in RTL. Should be this an errata? I think that it is very ridiculous... I am sleeping, but I can dodge or use some abilities. I think that is is pretty obvious that the original intent was that heroes could not do anything .

Is it correct?

Careful not to let your personal opinion cloud what you attribute to "the intent of the game designers."

Logic would seem to demand that a sleeping character can't do anything, at first glance. But is it really so illogical that a sleeping character could roll out of the way at the last minute and thereby dodge an attack? Besides which, Descent is known for numerous illogical rules, of which this is only one.

I think that as a house rule, saying heroes may do nothing while asleep is perfectly fine. It makes sense and I don't think it really cripples the heroes that much, considering attacking and moving are 95% of what a hero would want to do on his turn anyway. As far as whether it should be an official errata or not, well, it has been pointed out several times in the past. If they really wanted to fix it they've had opportunities already to update the FAQ, so if it's not already in there, then at the very least I think it's safe to say the designers are satisfied with the way its written now.

It should rarely come to the point where they aren't awake when their turn starts. Give two characters without ranged dice a bow or a throwing dagger and have one of them be the guy awake. On his turn he does a pittance of damage to the other one with a weak ranged attack (and a third guy if he can). Then that guy wakes the last one. You'll usually do 1-3 damage and have two people with full turns available.