Hi there,
I haven't had much time, but just to get the discussion going, this finds the boxes and colours them.
img = Import["~/Desktop/TestForm.jpg"];
SelectComponents[MorphologicalComponents[Binarize[ColorNegate@ImageResize[img, 800]]], "Rectangularity", # > 0.7 &] // Colorize
I have resized the image; note that the boxes in the first row, are often split into two parts because the "tick" cuts them into two.
Cheers,
Marco
