Sleek Photo Theme Sub-Pages & Attachment Pages

I’ve got Sleek Photo installed on one of my multiuser sites that I plan on turning into my personal portfolio. I’ve been setting it up with content from my existing static site, and so far, so good. I’ve set up sub-pages for things like the time periods of my Experience.

But I’ve noticed that when I hover over the “ribbon” menu bar while ON one of those sub-pages, the CSS (I think?) that’s supposed to indicate “you’re on this page already,” or “you’ve already clicked this link/a link that’s the same as this”, it appears distorted–that is, the background is a different color and not the same size as the menu bar item itself.

See it for yourself: and check out the “Experience” and “Portfolio” sub-menu options.

Secondly, I have some images that I want to display as thumbnails on other pages but, when someone clicks on them, go to an attachment page for the full-size image. I know I can make the thumbnail point to the media file itself, but I’d rather not, if possible. Is there a way to get this theme’s attachment page to show the image at full-size, rather than the thumbnail size? I’ve looked this up on the forums, but it seems to be a theme-specific thing, so I wanted to check here.