I'll ask what your skills are with LISP, I am not sure but I guess Lee Mac has limited what he did to text only, what would happen if you opened the file and changed the "TEXT" selection to say "CIRCLE", working through it you might need to change a couple of other parts too.
I suspect this might be best done in a few stages, get the easy ones working first - the block and the circle and then the rectangle where you'll need to also calculate its centre.
How much help you need of course all depends on your skill with LISPs - so what do you need us to do? can be from not very much to everything