What is it about montresor that makes him an especially effective enemy to fortunato?

they insisted that there was not enough time to learn everything.  

explanation:

if they were going to steal the answers that is simply because they insisted that there was not enough time to learn everything.  

no

glitch or non-saved account.

explanation:

i'm not personally a mobile user but one reason could be that it is either a glitch where it doesn't automatically log you in, or you have it so cant save your log-in information. i suggest you use the mobile app instead of using your web browser!

as for symbolic actions, the narrator's tearing down the wallpaper in an attempt to find the "woman" in the wallpaper represents her struggle to retain or regain her sanity.   the wallpaper has been part of her confinement and by her tearing it down, she is freeing herself from that confinement.