It looks like you are right NatCh. I thought the Reader turned on after pressing the reset but it doesn't.

I think I will reset it every time when I finish reading to see if it makes a difference.
EDIT: every time I reset and select a book the "continue reading" is showing page 199. The funny thing is I'm at page 235.
So it's not very handy to reset it every time because it's not easy to go back where you left.
EDIT 2: I found out what's going on. The Reader will bring itself to the state when you last connected it to the PC. I just connected it and after the reset it remembered my last page 235. Even the "continue reading" on the first page was pointing to the right book.