Blog Glitch and website speed

This is actually a two part question, but the original question has to do with whether there is a glitch regarding the original photography theme for HB themes.

For instance if you click the next button from the blog posts on the themes it doesn’t go to the next post or the previous post correctly.

http://hb-themes.com/themes/highend/photography/my-top-10-tips-for-a-brand-new-photographer/

if you go ahead and keep clicking next or keep clicking previous you will see what I mean. It doesn’t continue to progress or move back for the posts.

My second question is regarding the websites speed on my webpage. I’m playing with the HB photography theme and it seems to be very responsive. My webpage actually takes sometime to load, and it isn’t as responsive as the original theme. I wonder if this is because of the image sizes I’ve uploaded on the website. I was wondering if there was a specific size that is recommended for this theme.