I think you misunderstood me.
I didn't change line 132, the installer added a new row entry at the end of my existing spells.2da, but the Row label was still called "132". It also had the wrong ref for name and spelldesc columns, so I corrected the row number at the end to what it should have been (142 for me). I edited the script to say (142) also and it all works now. Looks like jc2 explained it thoroughly enough though 🙂