Featured Images of Posts not Adapting to Size

Hi: I'm using this theme for a Blog, it's quite good and I'm seriously considering updating to the Pro version in the near future. I've come up with an issue, though, previously the featured imaged of my posts were adapting on the Homepage where the latest post are shown. For some reason, it's no longer happening, in my latest post is getting cropped. I don't know how to solve it, look here please: http://www.charmfuldeadthings.com/ I think you'll see what I mean. Thank you in advanced for any help. Eduardo