help with plot layout

It takes a lot of sweat to generate a composite plot with R ...  sigh.
I though I was almost done when I met the umpteenth hurdle. I cannot place a nice title on the 2nd plot (raw signal)
on the layout. I do not have control on where either the "main" option of "plot" function, or "title", place the text
string which keeps dysplaying chopped from above. I also tried "text", changing many times the string coordinates, but could not see any text anywhere on the canvas . 
By the way, since the layout breaks the canvas into 4 parts, are the text coordinates absolute (referred to the canvas) or 
relative (referred to the part) ?
Please, find attached the generated drawing. The generating script is i the following.