I'm following the manual page 245 where it says:
But whatever I do, the Insert Index is grayed out. Apparently I have to do something special with the cursor? I have tried putting it at the end, after all the footnotes, but to no avail. Is there some special sequence I need to follow? (I am using "Index using word list," and it reports 280 hits.)Insert an index into your document
1. Put your insertion point (at the end of your document) where you want the index to appear.
2. Choose the menu command Tools > Index > Insert Index....
I must be overlooking something "obvious." Any suggestions?

Thanks, sorry to ask what presumably is a dumb question.