repeat structure

[barryb at libero.it]

Hi gang,
I am trying to make a repeat structure that deals with an unknown number of images located along a given line.
The line is the diagonal of a currently selected group.
How can I define that line and does it have to be actually be drawn before referring to it?

My attempts so far include:
-----
the rect of the selectedObject --the group
put the points topLeft and rightBottom of it into tSightLine

repeat for each image within tSightLine
select it
   the rest of my rubbish ........
------
Of course, the second line throws an error (unquoted literal) but I cannot find where to put the quotes it is asking for.

For some reason the script Editor does not colour rightBottom red unless the words are separated but then the error is Expression: bad factor - so I am leaving it black.

Any kind offers?
Barry