Sorry about the delay in replying mas, I've been doing the rounds visiting the folks.
The rust effect is very simple. I first started off with the shape for the "metal plate" on a layer, then I created a new layer filled the shape selection with a rust texture I already had, set that layer to overlay and adjusted the layer opacity to suit the effect, then linked and merged the two layers. Then it was simply a case of getting a screenshot of the Asylum, saving it as a pattern (edit>define pattern), then going to "layer styles>pattern overlay" and selecting the screenshot of the Asylum I have just saved from the list. I set the blend mode to "soft light" and twiddled with the scale untill I was happy with the positioning.
I can't remember where I got the rust texture from, But I always keep interesting textures like that whenever I find them. Quite often I go out specifically to take photographs of textures i think I might need, rust, walls, stone, etc.
I hope I have explained the method well enough to follow.
Cheers