Thanks Charles.

It was this line causing the problem:

Code:
IF (temp>=$32 AND temp<=$47) OR (temp>=$3A AND temp<=$40) OR (temp>=$5B AND temp<=$60) OR (temp>=$7B AND temp<=$7E) OR (t2b_word_length+index=t2b_focus_length) THEN
I'll expand it out into a number of IF statements and that'll fix it.

Cheers