Content does not show

Here a link to a post of my homepage

As you can see at this link, all media I try to include with plugins like Google Doc Embedder, NextGEN Gallery images include, iPaper…
Does not show the media.

It is the same for all of this plugins, that the will show the code segment for the include but no media/content.

I am sure that there is a simple solution but I don’t know for what I should search, and in which point the problems are caused.

Thank you so much!