First, selecting a field by relying on the index of your particular
docvariable seems obtuse, to say the least. The index numbers of your
DocVariables is just an artefact of the order in which you create them,
added to any that happen to be in your document already. Are you sure that
you're aligning the right paragraph, and how would you know? (And out of
curiosity, why such a bizarre approach?) -- Or do you in fact intend the
VALUE of the variable, rather than its Index?

Second, you're applying the alignment to the field code, when you should be
applying to the paragraph that contains that code.

Third, what is RTL ?