What dir should the showcase 3D slider files go in, in a MU install?

OK, owner of site #35 wants to maintain her own 3D slider images. What should I put in the "Image Location" field? I'm going to setup an ftp account so she can manage files under /home/unixacct/public_html/wp-content/blog.dir/35/ which gives her full access to all her uploaded content plus can upload and change her sliders. I assume the dashboard for each site has it's own settings so her stuff won't affect any other sites. Should I use the above path for "Image Location" or something like "./wp-content/blog.dir/35/" ???