Images are there, but they don't always show up.
Could this be a cache problem? Or Timbthumb?
Here is an example: http://designportugal.net/servicos/design/
And another: http://designportugal.net/portfolio/#all/3/list
I sometimes also have trouble getting into WP dashboard, it gives a warning php error, but when I refresh, it goes away and I get inside fine.