The dc's are caused by the AoE function too, because with speedhack the char has finished the skill before it uses the AoE again with about 200ms interval, and i get like 1 dc in 2 hours when im pressing the keys myself and then its using it even faster than with the auto AoE.
And the 64 items means 64 items any size, so you can have like 64 stacks of pills in inventory or 64 soes. And its for the whole inventory, not for each spot. You can try it yourself, put the stacker on and go buy some level 1 katanas or something cheap and count them until you cant buy them anymore.
EDIT: The recovery doesnt dc you, I can use it for hours when im training myself without any dc's.
EDIT2: Yea, the AoE-Multihit makes the dc's, i made that hack and gave to iktov. I have made a better version myself that wont dc you. The hack works just by multiplying the attack packets and will dc you because it sends too many packets to server in short time if you have too much monsters around.