Thanks orson.
I misunderstood the advice from others. I thought the advice was to add A to Longa, anagram of which is analog.
It took me a while to understand what to do with the extra words. But finally got it.
All seems to be OK. Except I have not found the extra word/s for 30d.
The grid is complete and the preamble gives away the final entry in the bottom row.