Responsive Update Version 8.0 not provided for in WP update?

Hi Guys,

I just found out that there’s a latest update for Responsive for version 8.0 (I’m currently still using 6.6.6), but it’s not reflected in my WP auto update feature unlike all previous version which have an update option when new one are release. So I went to download in my members area, i wanna update using WP theme upload features, but it says directory already exist, can I delete the main theme and upload? will all my work be gone? Cause I don’t wanna use FTP as i’m not very familiar with it. Any advise from the moderator or someone experience with this, thanks.